should i mention this is about the environment? it's a level for DOD:S. all (95%) content is custom made. characters and weapon models are still original game content supplied with the game itself.
Cesium offers pretty high res aerial imagery. https://cesium.com/platform/cesium-ion/content/bing-maps-imagery/ Beware though that all this data is copyrighted, you'd have to pay if you wanted to use it in a commercial product.
Or like Substance Painter but working in 2d space with pixel snap precision . Something simple like 2x2 ? Vector style maybe including vector curves to scatter small things along. With color range selection ? Something for quickly compositing materials from already existing pieces , not even any 3d preview is necessary but…