Reviewed:
Mastermind is an entertaining Isekai story where the main character ends up living in his favorite game world. All he wants is to live an easy noble life, but through a series of coincidences and misunderstandings, his life takes very different turn.
The plot is fun and engaging, I keep wondering what will happen next and although you can see some things coming, you keep wondering how the story will evolve further. One of the strong points is that despite the protagonists knowledge of the game world, he is far from omnipotent and has his flaws and weaknesses. This makes him much more fun to follow than if he could use cheats or become invincible.
Unfortunately, on the technical side the story is harder to read. It could use good editing. The sentence structures are at times confusing and sometimes sentences also repeat themselves. You can still follow the story decently, but sometimes it's a bit harder to follow than other times.
As far as my personal appeal goes; the scenes and characters that FantasyTranslater writes are a lot of fun to follow. The characters develop further too and although they're sometimes over the top, it works for this story. As of write now, I've read the first 46 chapters and that's what this review is based on.
I hope you all give the story a chance though, if you like Isekai stories, then you won't regret it.