That is not a legacy address, it's not a Multi-signature Non-segwit address either , it's indeed a P2SH-wrapped segwit address, how do I know? it's because that address has already spent some coins, otherwise, we would never know if this was a multi-sig or P2SH (we know it can't be a legacy P2PKH address just because it starts with 3).

You can check the transaction created by that address and you can see that there exist witness data in it which makes it a P2SH-wrapped segwit address.