Mooy featured heavily as Australia beat Syria over two legs to reach the intercontinental play-off against Honduras and Huddersfield manager David Wagner is pondering whether to rest his star midfielder.
Long-haul flights and extra time in the second leg in Sydney may have taken their toll on Mooy, while Danny Williams' timely return to full fitness could sway Wagner's thinking.
"A lot of managers in the Premier League have this sort of problem," Wagner said.
"Aaron has done very well in the past and we will come together to make a decision.
"He has taken the energy he lost on the grass, but got it back because he was with the national team and they took some steps towards the World Cup.
"We will see how he is. We are experienced enough to see if he can make Saturday's squad."
Williams has missed the Terriers' last three games due to a foot injury sustained in last month's home draw against Leicester.
"It's a perfect moment that he's back for the Swansea game and Phil Billing came back from Denmark Under-21s as well," Wagner said.
The Terriers, currently 11th on the Premier League table, have gone five league games without a win after taking maximum points against Crystal Palace and Newcastle United in their first two.
Their bid to bounce back from a chastening 4-0 home defeat to Tottenham before the international break has been boosted by news of a possible return for striker Steve Mounie.
Wagner confirmed club-record signing Mounie, out since early September, could be included in his squad.
"He has a problem in his heel and unfortunately it took longer than we expected and he got a setback against West Ham," Wagner said.
"Now we want to make sure that we don't rush him. We are happy that he's back in training. He's had a lot of minutes this week."