PSG should be able to qualify against Aston Villa. If they could qualify playing Liverpool, I don't see Aston Villa as a challenge for them. I believe they should secure a win both home and away against this said team.
Assumptions cannot be made in football just like that, because they won against the best team in the premier league this season doesn’t guarantee a win against a premier league team. They are two different teams with different strategies so it might not be the same outcome with Aston Villa.
For sure PSG looks stronger and are the favorites to win the game but Aston Villa is not an opponent that you can write off easily. PSG are in top form this season and they are almost unbeatable as they win matches with higher goal counts so Aston Villa would have to be at their best form if they want to have a chance to win PSG.