It's going to be dependent on non-free software.The only N chipset that is free software friendly is the AR9170 and the AR9271. The AR9170 is only available from us (libre.thinkpenguin.com) these days and the AR9271 isn't yet supported out of the box in Trisquel (it's coming though).
Stick with RTL8187B, RTL8187L, and the RTL8187 for now. Our Wireless G USB Adapter will work out of the box and work well with Trisquel 6 and uses the RTL8187B chipset.
