When trying to put items in the metal press with the gear press mold active using a hopper, the materials aren't going in the press. As you can see in the screenshots, iron, diamond and tin are in the hopper and none of them are going in the press.

Version of the pack : Enigmatica 2: expert skyblock 1.9b

Screenshots

The issue is, that the hopper tries to insert 1 item at a time, but the press doesn't accept a single iron as a valid ingredient. It works fine with things that insert all 4 ingots at once, ie the ME Interface.

If you don't have the tech yet, you can also add another conveyor on the input, so the hopper inserts to a normal conveyor and not the press directly. That should work as a workaround.