I'm kind of a noob on this Reddit, but I think I might just barely fit your criteria. I do rp DC and Marvel, but they aren't my main fandoms and thus I'm not huge on every bit of lore (you might even have to explain some things! Gasp!), but I'm willing to give a good effort.

As for DC, I currently have a role playing blog for Selina Kyle/Catwoman from a specific section of her comics that's all but dead but her muse is coming back to me, I've attempted Superman, I've been wanting to try a basic nonspecific Batman, and I'm sure I could pull off generic versions of most of the Batman villains and the original Robin.

As for Marvel, I've attempted Tony Stark with the most influence being from the MCU, and I have a few random mutant OCs that I'd like to do more with. Again, not a main fandom (less than DC honestly), but I have some friends who are much more into it that I could ask about things.

Beyond these, I have some independent OCs that I can usually work into anything with the help of AUs if you'd like.

I have a Skype if you'd be interested, if not, I'm sorry I wasn't what you were looking for and I wish you good luck!