oh god i have so many i could write a bible. of course many were already mentioned here, but i have to draw attention to some other artists.
my goat is yone kazuki. she basically raised me with hakuoki, though her more recent works are SO gorgeous. all the cgs in koroshiya to strawberry were just (chef's kiss), and her other projects are also as stunning.
the one that just KNOWS how to read my mind and understands me on a physical level is Kinako. she probably only did kyokai no shirayuki in terms of otome game, but oh man. her art is delicious. the way she draws legs and [man tits] is so [curvy] that you could straight up take a bite out of the characters.... and in a way, her men are always a little non-conventional, and 80% of the time you will see that they are wearing some kind of stiletto shoes. (insert "SHE'S JUST LIKE ME FR" meme)
since the game will be releasing just next month, shout out to Kazari tayu. her proportions are gorgeous and the detailing is oughhh.... hte way she designs is so majestic, her illustrations for yuugen romantica changed me as a person. go check out her v-tuber son Octavio from holostars, he's a cracked singer and terrifying.
and lastly, i think this might be a lukewarm take since people don't like her proportions a lot, but i would defend suoh (dairoku) with my life. her most recent artworks are so colorful and light at the same time, you can see that it takes a lot of skill to get this specific feeling. theirs drawings are beautifully stylized and a breath of fresh air in the otoge industry, in my opinion, even if they were hired for this.