Sure, but after awhile it gets super repetitive. Maybe one time confirm? Like I don’t need to hit, yes Confirm, 30 times to fully upgrade a merc. Yes, it’s minor, but it’s repetitive.
I don’t see it under Campfire, Shop, nor Crafting.
I haven’t even noticed… Maybe you’re right, but I dunno. Besides, it’s not like you upgrade mercs that often…
On PC (Windows), you go to the Campfire, at the lower right corner (to the left of the game’s settings button) there’s a field with a green ‘plus’ icon, a number indicationg your total Renown and a Mercenaries icon. There’s also a tooltip about renown if you hover you pointer there. You click there, just like the first time, and convert your excess coins to renown if you will.
[UPD]
Actually, the game asks a confirmation for upgrading equipment, but not a skill, as I’ve noticed with Rattlegore. This is indeed very strange and inconsistent… And I don’t remember whether it has always been that way.