Can you downgrade MySQL on a cPanel system?
There is currently not a supported way to downgrade MySQL on a cPanel server. We include more details about this in the top warning box in our documentation here:
While it may be possible to manually perform a downgrade, it would involve removing data and packages from the machine, which is not something cPanel support is able to assist with at this time. If you find it is absolutely necessary to downgrade MySQL on the system we recommend working with an experienced system administrator to help perform this task.