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Of the games you show here SuMa, CSL, EU4, HOI4, Stellaris and CK2 are all fully supported on Ubuntu and Steam OS. Vic2, EU3 and HOI3 are not; you'd have to use Wine.
CK2, EU4, HOI4, Stellaris, Skylines all run great.
Vic2 installs and plays fine on Ubuntu via Steam thanks to Proton, needs minor file renaming. Maybe Paradox could give Proton a little help to get that solved? https://www.protondb.com/app/42960