im not sure if it is afc vs nfc - it hasnt been for a few years now - i dont know if they've gone back to it
but if they have then...
still joe thomas is out, andrew whitworth is now in the nfc, donald penn hasnt been great this year, duane brown hardly played for the texans and now plays in seattle anyways, taylor lewan is still there but more than 1 tackle makes it per conference if it is a by conference system and of course villaneuva is also competition
and if not then still:
tyron smith out, jason peters out, trent williams has been hobbled all year, bakhtiari has been injured all year, taylor decker has only just been activated by the lions, terron armstead has been pretty strong as has andrew whitworth
so id say in the entire nfl this year ronnie's competition would be: whitworth, lewan, armstead, penn, trent williams (who might get in on name value but has hardly been able to practice all year), bakhtiari (who again has been hobbled all year but might get in on name value), villanueva (has the benefit of a big market and the standing for the national anthem in terms of fan votes) which leaves 8 left tackles vying for 6 spots in the pro bowl and id say ronnie has as strong a case as any of them... there's a couple of right tackles you could throw into the mix but generally right tackles dont go to the pro bowl...