PSG are just very lucky that they have one of the most comfortable draws in this stage. However Real Sociedad are still a team not to be underestimated. Because they finished their group as the leader and there was Inter in that group as well. Inter are currently performing much better than PSG in the Champions League.
Therefore PSG had better get well-prepared for this matchup. Otherwise I won't be surprised to see them being eliminated. In the end PSG were nearly finding themselves in the Europa League if it weren't for Milan's comeback against Newcastle.

I would be more careful with your wording about Real Sociedad. Inter Milan was not able to beat them at the Guiseppe-Meazza-Stadium and Real Sociedad was the team with more ball possession, which is really tough to do against Inter Milan when they play at home.
In La Liga they are not quite as good this season as I expected them to be, but still beating them is hard. Whenever they lose those games are tight games. I would not think that PSG will have two easy games against them.