In that minute or so footage, we see all new areas and Pokemon from even Sword/Shield. The only thing that it could be other than a sequel is a straight up reboot, which would still make it a whole new game. And since a general timeline for Pokemon Snap would be completely unnecessary, I cannot fathom why they would do that.
It's possible... Although HIGHLY UNLIKELY that it would be something like the original game remade plus a few new areas. I'm like 99.9% sure it's an entirely new game, but it could just be a very misleading trailer.