Seed swaps are where a lot of interesting regular genetics actually move around, because home made crosses rarely get a commercial release and the surplus has to go somewhere. Trust is the issue, since you are relying on the other person having labelled and stored things properly. Community etiquette for swaps, including what information to include with a trade, is summarised on https://breederregularseeds.com and it matches what the older forums have always said. Expect a few packs to turn out nothing like their description.