The go-to at the moment for pretty much everything: https://mhn.quest/
Armor set builder standalone: https://mhnow-builder.com/
MHN Discord with sets and some guides, bug reports, local meetups, etc.
And a Niantic dev present, for whatever that’s worth: https://discord.com/invite/monsterhunternow
I really don’t think, somehow, bizarrely, inexplicably, that niantic or capcom thought their built-in autistic monster hunter fans that do math for their damn video games were going to play this. They probably also don’t want people to know how it’s going to take 12k zenny and 6 rare 6 mats to go from 7-5 to grade 8. Probably would kill casuals spirits.