Keep in mind that you will be there in spring, so you should not wear too many warm clothes and in terms of style, Buenos Aires stands out as one of the trendiest cities in South America, drawing inspiration predominantly from European fashion. The local style gravitates towards classic, understated designs in solid hues, favoring subtlety over vibrant colors or bold prints. For travelers, seamlessly assimilating into this fashion culture can be advantageous to avoid appearing conspicuous as a tourist.
I hope I have helped.