Question about currency trading between GW and GW2

Hello everyone!

Like the title says, I was wondering if trading currencies between both games (GW and GW2) is legal? I would assume no, but I can't check ToS of both games atm. I've seen quite a few people post trade reqests in Kamadan where people offer GW1 ecto/gold for GW2 gold. I know it isn't safe as one can easily get scammed, but I just wanted to know if ANET is FINE with this method of trading between games.

I am really active GW2 player, but I wanted to finish my Obby armor on GW1 and probably get my last 5 HoM points and get GWAMM title (if that is what it's called).