The free 2018 FIFA World Cup Russia update is out now on PC, PS4, Xbox One, and Nintendo Switch, and we've played the PS4 version with no problems. It seems that this wasn't the case for several Nintendo Switch users, however. Reports of FIFA 18 crashing and freezing after the update have been circulating the Internet, but players seem to have found a temporary solution until EA fixes it themselves.
The problems seem to be related to the saved player profile, meaning it should work fine with a second player profile, or by deleting the personal settings on FIFA 18 (this does not include save games - phew). We haven't tried it ourselves, but still, it's worth a shot if you're having this issue.