Sure the J-xx can probably bomb buildings, ships and other surface targets if needed, but that’s really nothing special. You’ll struggle to find a fighter built in the last 40 years without at least some form of multi-role capabilities (okay we don’t have proof that J-20 can do A2G but that’s only if you go super strict and only accept things that are 100% proven and not things that are probably true). Again, with 6th gen defining it as a fighter or a bomber or something else doesn’t make a lot of sense since it can probably do a lot more than any single classification of combat aircraft up to now, so trying to call it a bomber makes not a lot of sense.