This is just an opening suggestion. Obviously things can change.
Assuming you can have inventory is on the left and nanoforge on the right.
Gamepad Y = exit screen(both)
left analog selects item
left/right dpad pages inventory (only crafting items are shown)
right analog selects nanoforge slot,
A=copy into slot
B=remove from nanoforge slot
Select=Test
Start=Craft
alternate gamepad config
Gamepad X = exit screen(both),
R1 & R2 pages inventory (only crafting items are shown)
dpad selects inventory items
right analog selects nanoforge slot
A=copy into slot
B=remove from nanoforge slot
Select=Test
Start=Craft