Thanks a lot! Adding fog of war from the 2D example to another kind of map is mosly about how you want to render it. There are simple ways to do it, but not all might look good. For a 2D hex map you could simply place down hexagonal black HISMs in the same way I do in the 2D example. For a 3D map you would want to be more creative. I mean, placing grey 3D hex meshes all over the map would work, but would not look good. You might be able to have them all share a seamless material with a cloud effect or something like that. Or you could play around with lighting or a post-process effect to keep unrevealed tiles dark or greyed out. Fancy rendering stuff is not my forté, though, so these are just suggestions for where I would start experimenting.
As long as you never begin the turn of the next unit after ending the turn of a different one, turb-based combat will be paused for all intents and purposes.