I don’t think there is anything in Star Wars that is socialist, maybe except some primitive communists and small scale utopians here and there (and definitely zero marxism), it’s one of those super common sci-fi settings where the horrors of capitalism are shown both in micro and in macro scale, but they are inevitable without alternative and the best people can hope for is to have relatively unmurderous liberal regime in place and some crumbs from imperialism flying their direction. At least untill the next iteration of Republic crumble into the next iteration of fascist Sith empire (that happened at least 6 times in expanded universe).

Its never stated outright but several factions operate in a very anarchistic or socialist way. For example in canon, Saw Guerra and his partisans were modeled very closely off of the Yugoslavian partisans in WW2, and it could be said that Saw is an anarchist in his thought, though his exact politics are extremely muddy. Funnily enough, his name is supposed to be a mirror of Che Guevara, and its very easy to see the similarity.

Or another major part of the Rebel Alliance were various CIS holdouts and defectors, which was a movement that included several planetary independence movements and organizations that wished to remove the corrupt nature of the Republic from their systems (even if the movement was hijacked and orchestrated by mega corporations and capitalists). For example the Onderon rebels during the Clone Wars.

An example of the previous scenario is pretty clearly shown in Cassian Andor, who starts off as a very aimless freedom fighter and criminal, but is influenced significantly by Karis Nemik and takes to heart his manifesto. Which reads as if it could have essentially been lifted right from Lenin’s writings.