Hey, this a song composed by Renato Borghetti the most famous accordionist from my home state of Rio Grande do Sul, the southern state of Brazil... we share the gaucho music styles with rural Argentina and Uruguay. He plays a button accordion... here I send you the link of the original album where this song is recorded.
Button accordion (bisonoric, diatonic) is my preferred approach to this music. However of course I'm dealing with the limited bass harmony. I've always wanted to graft a 48 or 72 stradella bass to one of my boxes, but have never gotten to it. (Instead, I play piano accordion half the time )