The player must be careful when swapping the hex:00 items with each other, as this attempts to merge the stacks the player has. Instead, the player may want to switch a different item in the desired place, before switching the hex:00 into that place.
Code
nopld bc,xx??
nop
ld hl,xx??
nop
ld de,xx??
nop
ld l,d
nop
ld (hl),b
nop
ret
This maps as the following items:
(hex:00 item) x1 (any item you want) x(value e.g. 21; Mew) (hex:00 item) x33 (any item you want) x(address byte 1; big endian e.g. 208) (hex:00 item) x17 (any item you want) x(address byte 2; big endian e.g. 88) (hex:00 item) x106 (hex:00 item) x112 (hex:00 item) x201