All variations, I definitely struggle with war god more than others but, Its definitely the footsie game that I have the most problems with. He has god like tools and covers a lot of ground in literally a blink of an eye.
You can nutcrack through every sword but the overhead, it's a 50-50 way in your favor. Get hit by the overhead and you get sent back and roll, block it and he dies. Same thing with low if you expect the overhead, definitely practice your punishes to be 100% consistent.
In any string, always block low the second hit and high the rest, he can only go low or overhead and it's always the second hit that's low and last that's overhead as a rule of thumb.
There's a particular range slightly closer than 3/4 where throwing F2 is uncomfortable because of the slow startup, find that range and you force Kotal to B1/F1.
Learn the F2 punish, IIRC cage punishes pretty good, look up the F2 punish thread in the kotal forums.
Prepatch it was difficult for kotal to catch you when you disrespected his + frames because he didn't have anything safe to blow you up with. B1 alone is not a real punish, B12 is punishable, B122 as well, F1 wasn't a punish, F12 and F1B2 were punishable as well.
Now F12 is safe. VS war god you still go through hoops because he can do things like B12 derp swords.
In the footsie range you just accept that he has super fast movement but they're all 1 hit unless he wants to risk going with something unsafe in order to throw out something that hurts, outside of traditional footsie range he has F2 for that.
But if he wants to open you up he has 0 way without exposing himself. All the swords are punishable on block except the slow one, his low F3 is unsafe, his B2 is reactable with armour etc.
I think the proper way to play war god is punishing things on reaction with the ex overhead, so don't jump, don't throw slow projectiles or anything of that sort.