Most of us weren't expecting him to be an armored trainee. Myrrh and Tiki at least were pre-established as trainees, and it would have made sense for Yglr to be a trainee (she isn't), but Surtr? The fuck?
Seems unlikely, as he has the severely reduced level 1 BST and huge extra growths of a trainee. Gen 2 units just have a little extra over Gen 1 units, not a radical rearrangement of bases and growths. Also, Yglr and Gharnef are both standard Gen 2 units.
Pokemon GO
Fire Emblem Heroes
Fate Grand Order
Dragonball Legends
Dragalia Lost
IV Calc
Heroes