I sold a G1 Megatron on US eBay a year or two ago. I don't know if they have changed their policies to completely disallow this since then.
Even if they haven't, you have to be really careful about how you display the toy. I did not show the toy in gun mode and had the auction yanked. I had to relist it with a picture of gun mode with an orange plug in the barrel. I ended up losing a bunch of bidders over that.
Thank you