Since the Black Hood was “killed” many episodes ago, we’re going off these assumptions:
1. The real Black Hood was never actually killed because Svenson was used as a fall guy, so the Black Hood is still at large.
2. Or the “real” Black Hood was killed, but he was working with someone else and now they’re doing the killings by themselves.
3. Or the Black Hood was killed, and now there’s a copy cat doing his bidding.
4. The person who is the “mastermind” behind Black Hood isn’t necessarily the person behind the mask.
5. Or, honestly literally anything else because this is Riverdale and anything is possible if you just dream it.