Well, to be honest, even the people who have seen Thor: Ragnarok can't quite call this yet, considering Justice League is dropping soon, so Diana also has new feats coming her way. Because, despite the fact that she has had a solo film, the only feats we actually have for current, present-day Wonder Woman is her part in the Doomsday BvS fight.
Wonder Woman's only advantage is her speed and how deadly her sword can be. Thor being a walking lightning storm now (Plus AOE attacks) render the speed factor not as relevant so it depends on how long Wonder Woman can keep away and approaches it.
Thor's far more durable and just as skilled so her sword is really the only way she can win but if the fight against Hela showed anything,
Spoiler:
it's that Thor can take a brutal stabbing and keep on going.