Am having the same problem with kb5031356, yet, the other kb5031224 downloaded and installed just fine and yesterday another update installed. windows update has tried to installed the update in question several times and failed. I downloaded the update from the microsoft catalog and tried to install it but it failed too. I tried all of the suggestions but found no problems. did not try to reinstall win10 because the other updates are working just fine and I got no errors with win update troubleshooter and sfc and dism. There is something about this update that is not compatible with my desktop win 10 computer yet it downloaded and installed successfully on my laptop computer. And my computer has plenty of space and memory.
This is an absolute disaster, the same problem as all of you and I almost lost the system. I am fed up, I am quite old, Engineer, and I have suffering from this since Windows 3.1. Last PC in my life. I will buy a Mac as my sons did. This is an almost 3000€ professional laptop, and this morning, it restarted at night, it was so a huge disaster the fans stopped and I found a nearly burning PC.