Inventory hoppers placed backwards against cables should extract from the system with the same ability for filter mechanics. Much like putting a hopper below a barrel can pull out, would enjoy to pull things out of existing storage. Or allow the open crate to push into inventories attached (like say a shulker box).

The Inventory Hopper should work both ways, but you have to set a filter to extract from the network.

ah. you're right. For some reason we weren't doing the right combo.