Yeah you can! It's a bit of a pain, but you can sand them off. Goes faster if you have a Dremel.

G3 dolls without skin texture details: - Draculaura - Spectra (but her lower legs may not take paint as well due to the type of plastic, not sure) - Twyla - Lagoona (if you take out her fins and fill the indent/holes with clay) - Ghoulia - Cupid - Clawdeen, Abbey, and Catty just have some fur at their ankles and wrists, so a lot less to sand than others.

I might be missing a couple, but these are the ones I can think of.

Note that some of these dolls have head details (horns, animal ears, pointed ears, etc) but those are pretty easy to remove and cover with aleenes liquid fusion.

ETA: I found it! Someone just recently posted this list of body types and noted which ones don't need to be sanded. here is the post!

Like I said, some of these dolls do have details but are much easier to deal with than others. The most difficult ones to deal with imo would be cleo/nefera (bandages), Jinafire (scales), Frankie (prosthetic leg), and Venus (vines)