Ok, here are some things I have in mind:

1. Delete part of the arms that are covered with the armsocks to avoid clipping. I know they do this for game character, but of course, it depends on how the character will interact. If she'll take them off at some point then this is a no no.

2. Use the Transfer Weight function in Blender, so that the armsocks have the same weight paint as the arms beneath them, which is what you need (I think) so they'll move together nicely without clipping. Or, use the Data Transfer modifier, which can do the same thing as weight transfer.

If I got the wrong idea about the problem, sorry .-.