Hi Borntobesting, I've just checked the memory and storage and it looks like there's plenty spare on both fronts. My WiFi download is consistently around 44mbps and just under 9mbps upload speed. I've also tried the game on a good mobile connection with no difference to how it performs.
I make sure no other apps are running in the background, even gone to the extent of clearing the WGT app cache and restarting my phone which sometimes helps with the sudden excessive bar jumps but makes no difference to the constant bar judder.
I've tried performance mode in the battery setting, changing the resolution and turning off the shadow setting in the WGT app, stopping gesture features and screen shot functions but nothing helps.
What's frustrating is a lot of other android phones have already had additional Android 10 updates a few months back but Huawei seem to be lagging behind on this. It might well be that the problem gets resolved after the latest version 10 update.