I’ve used a bin of construction grade sand.
Put the rechromed part in the container of sand, and gently knead the part around until the desired level of wear is achieved.
It puts random fine scratches in the chrome that doesn’t look like you back and forthed it with steel wool or a scotch brite pad.
The pressure used in the kneading process determines how fine or deep the scratches are.
Construction grade sand tends to have a more varied aggregate than beach sand, which also lends itself to the random nature you’re trying to recreate.