ecknz
I think this is coincidental, there must be something else causing the poor website performance. Maybe the server is i/o limited or the my.cnf is suboptimal.
Regarding slow phpMyAdmin with geographically diverse servers, it does depend a lot on the operation being carried out. General database admin should be fine but large SQL imports might be problematic. For example if you import an SQL file via the Enhance panel, it will upload the entire sql file to the web server and execute it locally as the website user and therefore it isn't sensitive to high latency. However, when you import with phpMyAdmin, I believe it executes each query individually. Therefore, if you have 0.1ms latency and 100,000 queries, the file would take 10 seconds to execute whereas with 50ms latency it would take 5,000 seconds or 83 minutes.
vsmbg In which version will this feature be released?
Unknown but it will be after version 12.0.0.