The idea would be to have the possibility to store more items than our limit, but block in relation to our inventory limit, if not very clear example

the inventory of my person is blocked has a limit of 145 usable items, so 145/145 in my inventory, I could store some for example beyond the 145, I could put them down and see them in my inventory, but I could not use them until I come back under the 145 limit or of course at 145.
This could make it easier to unload our messaging system and let's also imagine that some items (or mission rewards) could arrive directly in our inventory without having to go through the messaging system.
I think that would be very convenient at least for the mailbox!