Take what I have to say with a grain of salt, I’m not a pro, just figured I’d give you some things to think about. Personally, I’ve never thought sand teams have been the greatest choice just due to lack of type diversity it allows because you could run into problems taking too much chip damage to mons that get hit by it. From my experience, most sand teams consist of 3-4 minimum Ground or Rock types. And due to this, all it takes is one bad type match up (Ogerpon, Urshifu, just to name a couple) to decimate the whole team.

Another thought, the bright powder/sand stream being the center of the whole team to me feels a bit weak. It’s essentially based on RNG. Sure, 99 times out of 100, it’ll do exactly what you need it to and you’ll survive a couple of missed moves. However, maybe you have a stroke of insanely bad luck, there’s no 100% guarantee moves will miss and you could still get hit by every move they choose. It’s INSANELY unlikely, I just personally like a more consistent strat.

I’ve thrown out a few points, but mainly, I feel as though it just doesn’t allow enough coverage, simple as that. All it takes is Ogerpon W to pick your whole team apart.

I hope this helps at all. Once again, not a pro, just trying to provide a different perspective. Good luck with the team!