Yeah.Yeah. A part of the issue is that people try to shove non-D&D characters in D&D exactly as they are. This is not gonna work. D&D is very particular game with specific expectations. It's not a generic game for everything. Seriously, pick a game system that suits the thing you want to do.
Now, you can make D&D character that is inspired by these characters, but it's probably gonna involve significant changes. My main FFXIV character is Holmes-inspired, and she would work as a D&D character with minor changes, but in D&D she would probably be a necromancer or possibly a diviner. It is her personality and attitude that is Holmes inspired, not the exact things she does (she's a magical researcher and problem solver who's a borderline psychopath and a genius with a superiority complex, using questionable and unorthodox methods.) Though as I noted earlier, you could do more direct Holmes in D&D as an inquisitive rogue. Sure, it would probably bump combat power a bit (though Holmes was no slough in combat) but that's just because in D&D every character is weirdly competent in combat.
But it's also stupid that every smart, wise, or charismatic adventurer in D&D used spells to bypass obstacles or is a sneaky backstabber attached to criminals.