Having a similar issue.
3 of us in the same home playing co-op on Switch. Online, not local.
Host playing docked, hardwired in via cable.
Me and player 3 playing handheld via wifi.
About every five minutes I'm just not allowed to move. Game goes on around me. Sometimes I'll freeze while the host isn't freezing, and he'll freeze while I'm not freezing.
@tommybob, there's no rubberbanding in my situation. The game seems to be going on as normal, like I'll be getting attacked in the mines, or fishes will get away.