Tensei shitara Dainana Ouji Datta node, Kimama ni Majutsu wo Kiwamemasu

Reincarnated main character just vibing and getting stronger, Knows its target audience and delivers on every important aspect for it 

both anime about a reincarnated shouta with adult mind, who is fascinated by magic and has his own harem  

Both protagonists are reincarnations and excel in magic. They both try to somewhat hide it.  

Reincarnated main character just vibing and getting stronger, Knows its target audience and delivers on every important aspect for it 

Reincarnated main character just vibing and getting stronger, Knows its target audience and delivers on every important aspect for it 

They have a similar ratio of messed up, fun and wondrous in them, though each are very much products of their era. 

both have young boys as the main charater who is obsessed with some fantasy element, in knights and magic is mechs and in 7th prince its magic. both of them are extremely talented in there areas and tend to creep people out with how focused they are. both improve there areas in ways no-one has thought of before both have MC's that kinda look like girls. both are set in a magical fantasy world where the MC's get reincarnated to live out there otaku dreams in there respective fields. 7th prince has a lot more ecchi stuff then K&M witch has no ecchi things.  

Reincarnated main character just vibing and getting stronger, Knows its target audience and delivers on every important aspect for it 

Both the main characters are overpowered, small, blue-haired, and exude chaotic cinnamon-bun energy. Both shows are set in a fantasy setting and are comedies.