The character creator in Monster Hunter: World is quite in-depth. With enough time and patience, you can customize your Hunter until they look like an action hero or anime character of your choosing. It's not as fun as importing them into the game itself, confused and screaming, but it's still fun.
Why not start by turning your Hunter into Geralt of Rivia from The Witcher games? I feel like the titular Witcher would feel right at home in the untamed wilds of Monster Hunter: World. The process is easy enough thanks to "DeadlyxElements" on the Monster Hunter subreddit. They've written down step-by-step instructions, including which facial pre-sets you ought to pick, and where you need to position your sliders to get that extra-gruff Witcher glare.
DeadlyxElements says they're going to make and share more custom characters in the future. If you want your avatar to look like Joey from Friends someday (just spitballing ideas, here), it might not be a bad idea to ask Capcom about that Monster Hunter: World character do-over option after all.
While not quite the same creation, we've embedded a YouTube video of a similar Geralt character being made in Monster Hunter World that should be pretty easy to recreate.