There are some misleading bits of info being given here. Here are my answers which I’m pretty confident in. XP buffs (+x xp per kill or +%xp) are shared across the party. This makes leveling in a group pretty advantageous. This is observably testable by having one party member equip a red gem in their helmet. They will not gain levels faster than their comrades assuming everyone is participating equally- rather everyone will level faster. When deaths breath and GR keystones drop, the loot will be personal but equivalent for everyone. For example, if you see 3 DB drop for you, 3 DB will drop for someone else- however the DB that you see are 100% yours and you should pick them up. All weapon and armor loot is personal and will roll according to which class you have. It is possible that you will get items to drop that aren’t with your main stat or for your class, but that is random and rare. Loot can be shared between eligible party members (if they were in the game when it dropped and were active in whatever activity you were doing).