I'm fairly aware that merc contracting is widespread, though I wasn't aware that they were widely used in the Liberal Wars. The point was that I couldn't think of any time where they were praised for their service, but now that you mention it there were many mercenaries involved in the independence wars in Latin America. Including ours, no matter how short it was. The most distinguished one that comes to my mind being Thomas Cochrane. But there might have been more rank and file soldiers instead of, well, adventurous European nobles with fuck all else to do.