considering there are over 300,000 asian argentines, at a bare minimum, and most live in Buenos Aires, there is no reason an asian person would "stick out". there are tens of thousands each of koreans, japanese, and chinese living here.
I see asian argentine every single day, I work within a few blocks of 5 or 6 asian restaurants, and pretty much every corner store is run by asians.
no worries there.
What "sticks out" is rolex watches, large expensive cameras, gigantic iphones, gold jewelry, mercedes cars and the like- ie, obvious signs of wealth.
day to day, BA is one of the safest cities I know. I have at various times in my life lived in Seattle, Halifax,Washington DC, Chicago, Mexico City, and LA.
I think BA is safer than any of them, for the average citizen or pedestrian.
I am 69. I walk everywhere, take the bus almost everyday, and have been to a lot of the poorer barrios, ranging from La Matanza to Flores to Villa Soldati and Avelleneda- all places its extremely unlikely you would ever go. Never a problem. I dont look rich, I have decent street smarts, and I have never been hassled, in 15 years of wandering greater BA.
Dont over think this.