Faceit ToS say you cannot have multiple accounts. As a result, if they find you do they will ban one (or both) of them. However, faceit support staff do not have the authority to ban accounts (most of them are random volunteers), so it takes an actual admin to do the banning, and they most likely won't hear about it unless, as you said you are evading some sort of ban, or you are trying to get multiple accounts into fpl etc.
You don't have to pay for faceit, it offers a free matchmaking service, but there are two premium packages that give you various things, but you don't have to pay. Esea on the other hand, you have to pay for.