>>534268696
That's what they did though lol
I outlined it here and in a few other posts if you want to see all the info we got through press and sources and stuff
>>533490059

Here as well is some more stuff about it
>>>/v/717205789
>The map creator uses Godot. You can create and import new geometry, modifying existing geometry, modify AI scripts, make custom UI, adjust camera settings. You can create new rules and design entirely new gamemodes.

So yeah, we have examples of new gamemodes using stuff like custom AI and totally custom UI to recreate COD zombies (they don't call it that but it basically is), from the unleaked EA fact sheet about the BF6 editor and that's that
We get Godot as the base that sends off the level files to be interpreted by the engine, instead of a Frostbite in-house tool turned into a public version editor, is probably to do with confusion or hang-ups over the actual Frostbite licence not letting them