If you're visiting Osaka on your own and want to eat seafood and explore a market, Kuromon Market is another attraction that many tourists include in their itinerary! Known as “Osaka’s Kitchen,” Kuromon Market offers all kinds of seafood, wagyu beef, fruit, and seasonal ingredients. Along the way, you'll see plenty of freshly cut seafood, grilled seafood, and various snacks. You can eat as you walk and take in the lively market atmosphere.
However, after actually walking around, I felt that there really were a lot of tourists, especially visitors from other parts of Asia. Quite a few of the shops are also run by Chinese people, so the whole place feels very touristy.
Compared with Tokyo's Tsukiji Market, I personally think prices at Kuromon Market are a little lower, but they're still generally tourist prices. If you want a good deal, I recommend comparing several shops before buying instead of immediately purchasing something as soon as it catches your eye!
If it's your first time in Osaka, it's still worth stopping by to walk around, see the market, eat some seafood, and experience Osaka's lively everyday atmosphere. But if you're expecting the feel of a traditional local market, you may need to adjust your expectations a little!