The 22-year-old Glasgow-born midfielder has been on Wenger's radar for months, with the Frenchman a long-time admirer of McCarthy's talents.
Moyes, on the other hand, is keen to bolster his central options. Chelsea are eyeing up Marouane Fellaini, who has a £22million buy-out clause in his contract, as a possible replacement for Frank Lampard and McCarthy is top of Moyes' list if that happens.
In December, Wigan boss Roberto Martinez said that McCarthy was destined for the top but would be better learning his trade at the DW Stadium for a few more seasons before making a big-money move.
Both Everton and Arsenal would be prepared to shell out £8million for McCarthy but Wigan may hold out for £10million.
Liverpool are another club reported to be interested, with McCarthy fitting the profile of the emerging talent that Brendan Rodgers and Fenway are targeting.
There have also been reports that Richard Dunne could be on his way stateside to join Robbie Keane at LA Galaxy.
Dunne, currently sidelined with a hip injury, had been linked with a move to the New York Red Bulls.
But it's believed that the current MLS champions are now leading the race for his signature.