Switching my gear presets causes me to lose stats (attack power is the only one I noticed) and my gear set bonuses. I use the exact same armor setup just different accessories to match a different build (igniter vs reflux sorc). At some point they do return while I play, but I’m not sure when or how (and it usually persists for a few runs of any content and I switch often). Problem is avoidable if I just never switch presets but they exist for a reason I assume and it is a major QoL if they worked.