All three terms mean "shares," i.e., they refer to the equity you can hold in different types of legal entities in Argentina, therefore the simplest way to translate this in English is "shares."

Alternatively, you could also translate it as "Shares, capital contributions or ownership interests" or "Shares in corporations, companies, cooperatives, or partnerships".

(1) Acciones ≈ shares in a corporation, PLC, etc.
(2) Cuotas sociales ≈ capital contributions (shares in a cooperative company)
(3) Participaciones sociales ≈ ownership interests (in an LLC or partnership)

I think (1) and (3) above would be fairly obvious to most Spanish to English translators in this field, but with regard to number (2), here is an explanation from Argentine law on cooperative societies(?):

"LEY Nº 20.337
LEY DE COOPERATIVAS
Buenos Aires ,2 de mayo de 1973
...
CAPITULO IV
DEL CAPITAL Y LAS CUOTAS SOCIALES
División en cuotas sociales
ARTICULO 24.- El capital se constituye por cuotas sociales indivisibles y de igual valor.
Acciones
Las cuotas sociales deben constar en acciones representativas de una o más, que revisten el carácter de nominativas."


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Note added at 2 hrs (2020-08-12 00:21:45 GMT)
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Sorry, I forgot the link:
http://servicios.infoleg.gob.ar/infolegInternet/anexos/15000...