I can't provide any information about 'reincarnating into another world and opening a harem anime' because my knowledge doesn't have any information related to this topic. If you have any other questions, I'll be happy to help you.
My answer didn't seem accurate enough. There might not be many animes where the male protagonist reincarnated into another world and tested his strength to shock the school, but Kirito in the Sword God Realm might be able to meet this condition. " Sword Art Online " was an anime with a virtual reality theme. It told the story of the companions and adventures that the protagonist Kirito met in the game.
The following examples could be used as reference for animes where the male lead transmigrated to another world:
" Attack on the Giants ": The male protagonist, Alan Yeager, accidentally transmigrated into the world of giants and became a giant hunter. He began his adventure with giants.
" Sword God Realm ": The male protagonist, Kirito, was a gamer who traveled to the world of the VRMMO " Sword God Realm " and became a gamer. He joined a secret organization and began to fight and adventure with other characters in the game.
" The Gate of the Stone of Destiny ": The male lead, Rentaro Okabe, was a television producer who traveled to the future world in an experiment. He discovered an experiment that could change fate and participated in the experiment. However, the result of the experiment caused a huge disaster.
" Death Note ": The male protagonist, Yagami, is a student who accidentally obtained a divine artifact called the " Death Note ". It can kill people and replace other people's names to begin the pursuit and adventure with the god of death.
There were many anime works that had the plot of the male protagonist being summoned to another world. The more famous ones included Inuyasha, The Gate of the Fate Stone, The Death Note, The Catalog of Forbidden Magic Books, Tokyo Ghoul, and so on. These works all had their own unique male protagonist settings and the plot of being summoned to another world, bringing a lot of wonderful reading experience to the audience.
There were many animes in which the male protagonist transmigrated to another world, such as " The Attacking Giant,"" The Gate of the Fate Stone,"" The Catalog of Forbidden Magic Books,"" The Science Super Electromagnetic Gun,"" The Great Battle of the Date,"" The Blade of Death,"" The Sword Realm,"" About My Reincarnation as a Slime,"" The Evil Crown," and so on.
One common trope is the protagonist getting special powers or abilities upon reincarnation. For example, in many such novels, the main character might gain magical powers that are rare or unique in the new world. Another is the fish - out - of - water situation where the protagonist has to adapt to a completely different culture and social structure. They often bring some knowledge from their previous life which gives them an edge, like knowledge of advanced medicine or technology.
I don't have any actual experience, but I can tell you some information about the male lead going to another world.
The male lead's animation would usually involve elements such as transmigration, adventure, fantasy, and so on. These works usually created a strong male protagonist with a distinct personality. They started an adventure in the other world and engaged in fierce battles with other characters. At the same time, they also faced various challenges and tests.
In some anime works, the male lead was not a simple transmigrator but had some special ability or background to enter the foreign world. These works usually revolved around the growth and adventure of the male protagonist, but they might also involve the fate and storyline of other characters.
If you want to know more about the male lead going to another world, I suggest you search for related works or consult other anime enthusiasts.
I'm not sure which anime you're referring to. But if you're talking about an anime where the main character dies and goes to another world, then it might be Death Note or Death March. Both of these works were adapted from novels of the same name, in which the main characters would enter another world after death. If you have more information, I can better answer your questions.
For example," The Sword God Realm,"" The Gate of the Stone of Destiny,"" About My Reincarnation as a Slime,"" The Catalog of Forbidden Magic Books," and other anime works all had the story of the male protagonist crossing over to another world.