you could- use a light weight fusable that does not need too hot of heat (don't want to melt the socks)
a lightweight interfacing might help keep them from stretching out of shape for sewing.
were you going to use the socks whole? or cut them in half=so only one layer?
if using them whole---two layers----i wouldn't use an interfacing too===just a fusable- use a needle for knits- and a larger stitch length than what you normally use- go slow to keep from stretching them as you sew.
if using one layer then an interfacing could be used- you could get a fusable interfacing- stitch it all the way around the sock (fusable side to right side of sock) then cut a small slit in interfacing so you can turn it right side out- and fuse down- then stitch to background.