I have 1920x1080 resolution on Win10. When I tried to start VCMI (with essentials for resolutions installed), I got crash with SDL report that only 1280x720 availiable. But it didn’t start even in 1280x720 as “SDL says that resolution 1280x720 is not availiable”. To force software renderer didn’t help as well. Only resolution I was able to run is 800x600.
It looked like SDL truly reports something wrong to the game. I googled it, and it appears to be a known problem. Thing is that if you set screen zoom like 150% in Windows, basic system methods of resolution querying start to report wrong numbers.
So, temporarily solution can be to switch back system screen zoom to 100% - then all works OK. But it seems that it should be fixed in software using some of the approaches that are described in the link above.