Freezing or vacuum sealing fish
I freeze all my game meat (mostly turkey and waterfowl) in plastic wrap and I have had no problems up to a year.
One thing with vacuum sealed anything is to cut the bag open to break the seal before thawing (or unthawing as it is typically said in WI). Thawing anything while still sealed in a vacuum will suck the moisture out.
I don’t typically keep enough fish to have a need for long-term freezer storage but I have noticed that fillets don’t keep as well in vacuum sealed freezer bags as they do in a block of water. I had cleaned enough bluegills a year ago in spring and froze them in a Ziploc bag full of water for a party last summer that never happened. I thawed them for a fish fry this past weekend and they were still very good. I wouldn’t have tried that with year-old vacuum sealed fish.