Iver is a dragon maou who stopped trying after historical heroes defeated her every time she resurrected. But the present day hero, Mirio, who found the holy sword by pure chance falls in love with her. And thus forms the couple of the maou with no self-esteem and the dopey hero. This is a story of how they come to know each other, fight, and find happiness.

Aizawa Yuri has reincarnated 2 times now and is dead tired of being the emperor of this and that. Using his skills he acquired a reincarnation artifact, and starts his life in a brand-new world!

Hidako Masamune is a high school student who suffers from continuous bullying by his classmates. Becoming tired of it all, he decides to commit suicide, but instead he is transported to another world along with all his classmates. When they arrive, they find that they now possess amazing abilities, but he was only granted the status of a "healer," the weakest skill of all. The king decides to get rid of him by transporting him to another far away place, but not before Hidako swears revenge against the king, the kingdom, and all of his classmates.

From MangaHelpers:
29-year-old programmer Suzuki Ichirou finds himself transported into a fantasy RPG. Within the game, he's a 15-year-old named Satou. At first he thinks he's dreaming, but his experiences seem very real. Due to his use of a 3-time-use special power (meteor shower), he ends up wiping out an army of lizardmen and becoming very high level. He hides his level and plans to live peacefully and meet new people, though developments in the game story (like the return of a demon king) might get in his way.

A 34-years-old NEET otaku is chased out from his house by his family. Unattractive and penniless, he finds that he has reached a dead end in life and realizes that his life actually could have been much better if he had made better choices in the past.

Just when he was at the point of regret, he saw a truck moving at a fast speed straight towards three high schoolers in its path. Mustering all the strength he had, he tried to save them and ended up getting run over by the truck, quickly ending his life.

The next time he opened his eyes, he was already reincarnated into a world of sword and magic as Rudeus Greyrat. Born to a new world, a new life, Rudeus decided that, "This time, I'll really live my life to the fullest with no regret!" Thus, starts the journey of a man yearning to restart his life.

『The Overwhelming Adoration of the Sweethearted Lady!』

Alicia Ozrind, known in noble circles as the Frost Duchess, is feared for her cold and unyielding demeanor, earning her the reputation of a villainess among the aristocracy. But beneath her icy exterior lies a girl who simply struggles to express her true feelings. There is, however, one person who has melted her frozen heart—a young servant named Gray, who works as a cleaner in her grand estate.

"You’re the only one who truly understands me!"

Completely smitten and vulnerable around Gray, Alicia showers him with unrestrained affection. Whether it’s during meals, in the bath, or even before bedtime, her overwhelming sweetness knows no bounds! But their relationship isn’t without its hurdles—Alicia is a noble lady, and Gray a mere commoner.

Will Gray manage to endure the relentless love of this endearing aristocrat? This is a sugary-sweet, heart-melting romantic comedy set in a fantasy world!

Sozai Shuu, a working adult with a slightly weird habit of loving to collect raw materials, was transferred to another world by God after losing his life.

In order to live leisurely, Shuu wished for 『a power to live a carefree life collecting raw materials in another world.』His wish was successfully granted however, his magic power is strangely enormous, and his skill is really convenient? Seems like God misunderstood that he wanted to harvest materials from monsters leisurely so the power he gave Shuu was so incredible….

Nevertheless, Shuu does not take it to mind and freely uses his unique skill 【Detect】 in another world to search for materials, harvest them, eat them, make money off of them and lives a carefree life collecting materials.

Dirty oldman isekai

Fantasy harem-comedy begins with a kind-hearted uncle who helps the weak, crushes the strong while doing some consensual seeding here and there.

Love Momozono is a 14-year-old student at Yotsuba Junior Highschool that tends to care more for others than for herself. One day she visits a show of the famous dance unit "Trinity" and decides to become a dancer, too. On the same event, subordinates of the Labyrinth Kingdom show up who want to collect the unhappiness of the audience. Love gets the power to change into Cure Peach and fights them. Soon after, she is joined by her good friends Miki, who is Cure Berry, and Inori, who becomes Cure Pine.

The story is set in the modern world, but there exist doors that can take people to the "other side," where strange urban legends and internet stories prove to be true. College student Sorawo Kamikoshi finds herself exploring one of these doors, and almost dies on the other side, when she is rescued by another girl named Toriko Nishina. Toriko is mysterious girl, but very skilled with a gun, and she seems to be searching for someone else on the other side. Together, both girls start to explore these doors to the other side.

Mitsuki Kou is such a feared PVP gamer that he's earned the nickname "Crim the Headhunter" in some circles. His next game to take over? "Destiny Unchain Online", a brand new VRMMO game developed by none other than Kou's father. But, no new game on release day is without its bugs - namely, Kou glitches to the middle of nowhere, and his vampire avatar is turned into a girl! A story for all of the people who through games have met new friends and aimed for the top... start!

After his unfortunate death, Tomokui Kanata has been reincarnated as a member of the weakest race, a goblin named Rou. However, Rou has retained his previous life's memories, as well as an ability that allows him to gain strength and abilities from eating. He also possesses a unique evolutionary tree.

Now, Rou has made a promise to himself that he would live this life to the fullest. In this alternate world of survival of the fittest, events unfold with competent subordinates and comrades.

Orginal Webcomic

A man who was once called the world strongest agent ended up becoming a teacher after his retirement to train the new generation of agents. After many years of training his disciples, he is killed at the age of 60 by the ploy of a secret organization and was reincarnated in another world with all his past memories.

Though he was surprised by the magic and the strange species of that world, he adapted very fast to his condition as a newborn and took advantage of it. He acquired special magic and gained a massive amount of strength thanks to his tight discipline, in order to reach his goal: Resume his career as a teacher which he left halfway through in his previous life.

This is the story of a man, who, based on the memories and the experiences of his previous life, became a teacher who travels through the world with his students.

The virtuous will definitely be rewarded!

This world judges the deeds and good karma of your previous life, and grants you a rank when you are reborn. The benevolent man, even surprising the gods through this, decides to be reborn as the son Alexander of a noble family, and thus starts his SSS-Rank life! Follow Alec's journey as he lives his life as a SSS Rank!!

The world is not perfect. Learning to deal with its flaws is just a normal part of life. But there comes a point where these imperfections spawn a crushing realization... that something needs to change...

This is a story of a 29-years-old bachelor who was brought to a different world to live freely. Caught by an “unwanted” wife from day one, his life is not going so smoothly when the entire country focuses its attention on him in ten days. Without losing to such an obstacle (?), he will continue to live on.

Kosuke found himself in a whole different world. WHAT?
Standing there with the wilderness to the east and a forest to his left, he decided to make good use of the occurrence, and tests his knowledge, to where he finds this amazing crafting ability, just like the games from his orginal world!

Six years ago, Natsuki Yura was summoned to another world as a hero. After defeating the Demon King and finally managing to return to his original world, he discovered that Earth was actually full of fantasy too—psychics, aliens, angels, gods, you name it.

Realistic take on a modern doctor in another world treating fantasy creatures without magic or modern equipment

Losing his memories, the curtains of the story of alternate world transfer of the MC rises. After the transfer his name changes to Kelvin. While steadily levelling, he adds new subordinates by mastering his skill. And by the time he noticed it, he had obtained overwhelming power. Where will our MC be heading off to?