I think it would really depend upon who you RP with. Some people might frown upon it, considering it to be the stuff of Fanfiction.net (AKA Mary Sue territory) ... while others might actually be okay with it.Â
I'd personally recommend looking for RPs that don't care about sticking to the lore, personally. Because as I've personally noticed, a number of RPs like to stick to the lore (or at most "bend" the lore). If you can't find an RP group that suits what you're looking for, then I'd just ask around for help regarding things pertaining to lore. You can also go through the storyline quests, picking up on the overall rules of the world (and the cultures within) isn't too hard after a bit.
I'd personally recommend looking for RPs that don't care about sticking to the lore, personally. Because as I've personally noticed, a number of RPs like to stick to the lore (or at most "bend" the lore). If you can't find an RP group that suits what you're looking for, then I'd just ask around for help regarding things pertaining to lore. You can also go through the storyline quests, picking up on the overall rules of the world (and the cultures within) isn't too hard after a bit.