The “Buff to Give Owner Character” on items ONLY works for consumables.
For weapons or items like armor, you would need to create some graph logic that triggers from the “Event Blueprint Equipped” event (for armor) or “Event Begin Play” (for weapons) to add your main buff. “Unequipped” for both to disable.
On the main buff, simply add some input keys that will toggle the other buffs like weight, speed etc.
The bug repellent lowers the aggro range on certain dino’s so you can get closer before they aggro. It does NOT actually make you invisible. For that you would need to use a “toggle” or “set visibility” node for the character mesh. However, keep in mind that even if the mesh is set invisible, I’m pretty sure the dino’s will still “sense” you which is why you’d want to make a repellent too.