This one is for the full mods/staff I guess, if I suspect two accounts on this site to be owned by the same person, is there someway to communicate that so a full mod can look into that? Is there maybe a thread for that already? Or is that maybe (a) not relevant or (b) not against the site rules? (since it's "just" kind of a secondary account and not ban evasion). Just curious, thanks in advance :)

As long as one account isn't banned for doing something, then having alternate account isn't against the rules. If however they are using the alternate account to circumvent a ban then it is against the rules, although you'd likely not know they were the same person unless they did the same stupid things.

I think they should only have one record for a game between all the accounts though, so both accounts can't have a record for Game X any%, but it's something you'd talk to game mods/site staff about.

There is no full mod named "Ro". But yes, contact one of the staff directly if you think someone is sockpuppeting or ban evading.

Alright, thanks for the quick answer :)