What if instead of Italian immigration, there was French immigration to Argentina? What if Argentina was the destination of French migrants instead of Algeria? What if the backbone of the Argentine society were French and Spanish people instead of the Italian and Spanish people? Would they get along? What if Juan Bautista Alberdi succeeded in this plan and actively pushed immigration of people from France?
Effects
1) Would the country have a stable government with influences from Northern Europe?
2) Would the country do better economically?
3) Would the country become a great power like France and Germany and ally itself with NATO and the west?
4) Will Peronism not have existed in the first place?
5) Will the country have a better military and captured the Falklands? Would its military be as powerful as France's or Germany.
6) Will society be even more racist towards Bolivian, Paraguayan, and Peruvian people.
7) Would society be more secular or would it still be a Catholic country? Would the population grow?
8) Will it get involved in both World Wars. If so, Axis or Allied? Would it get involved with the Axis powers just to recapture the Falklands?
9) If Argentina ends up a success story, how would it affect Brazil, Spain and the rest of South America? Would South America be peaceful?
10) FINAL QUESTION: Will the country diverge from South America and be more culturally closer to the West?
I know this is really in depth.

Good luck