The centre-half is back in Sweden after spending a week with the Swans.
Papagiannopoulos told Ostersunds-Posten: "I trained with their first-team squad for a few days and got to play an internal game with some younger players, plus Swansea's substitutes. It felt good. What impression I made is up to Swansea. My hope is that there will be more, but you never know in this context.
"The Premier League is tough, but I think it would suit me. The pace was no problem during the training sessions in Swansea, though I think that match the tempo in the English top league is something else entirely. But it would be fantastic to possibly try out this sort of challenge."