It's quite possible. I've never personally seen it but I have seen many variants including Maxcy, Maxcey, Maxe, Maxi, Maxie. Macksey, Macksie, McSey,amd Maxaye. One researcher also reported a MacKessey. Family historian Edythe Clerke Maxey said that Massey amd Massie are different families but did not comment on Macey/Macy.