Almost all the second half of the Wonder Woman movie sets around a fictionalized village of Veld, in Belgium.

Although on a map [timestamp 1:22:38] Veld it is indicated next “Hazebrouck”, witch actually is a village in northern France, the script and the dialogues clearly indicates the story happens in Belgium: in the War Room of the International War office [00:58:20] :

COLONEL DARNELL: “Ludendorff was last seen in Belgium.”
GENERAL HAIG: “We can’t be seen sending troops into German-occupied Belgium as we are negotiating their surrender.”

Diana (Gal Gadot) has a few sentences in french with Sammy (Saïd Taghmaoui) [01:03:25]. In the No Man’s Land, Diana speaks (one sentence of) famish “Waar is dat gebeurt ?” [1:13:10].