The create does not allow for the transfer of items between the portable storage interface. Specifically with trains. No items transfered and deposited into the item vault or chest of the train. This seems to be a bug since I tried it on both my personal server and on a single player world.

Yes but how does that work on a train?

If you just have a chest or vault on the portal storage interface it wont work. You need to extract from them. This can be done using funnels or chutes coming from or going to the portable storage interface.

Because I noticed that the portable interface is the only way to transfer items between the train and any other point. And it is not working at all.

in theory, you either pull out of the stationary interface to remove items from the train or push into the stationary interface to put stuff into the train. I havent used trains but have found that fast moving contraptions can skip the interface interaction

looks like it may be upstream though Creators-of-Create/Create#3408 (this is the forge version that the fabric version ports from)

If you're unloading from a train, you pull out of the stationary interface and if you're pushing onto the train you push into the stationary interface.

So Im able to load with the hopper strategy you provided me with, but now Im unable to unload it