Please add invsee again because i don't trust people enough not to have to spy on their inventory if i lent them something
I don't know if this feature will be added again. However I feel like they shouldn't. If you lend an item to someone there is a small chance they won't give it back to you. When a player doesn't want to give it back, you can always inform staff. Also adding that command back doesn't mean you will actually get your item back. You can only check if the player still has it. I personally don't see the point in adding a command which allows you to check where "your" item went. On a side note, I don't know if staff can force the player to give it back to you. You dropped the item on the ground or gave it by using the trade system. That way it is 100% your fault since you "gave" the item.
If you don't trust people do what I do. Screenshot exactly what is being lent,traded , with the other player agreeing they will give it back. Then take a small video/several screenshots of you trading the item with them. That way you will always have sufficient evidence should the player not give you back your item.
If you don't trust someone, don't lend it to them. Honestly I was really annoyed when players kept peeking into my inventory, I don't need to know my inventory is messy nor do I want their comment on it. If I have something they want, they ask for it. I prefer it being removed. Oh and, you don't "need" it, you just want it.