You can uninstall everything with a version number lower then 8.8.0
Please not that v5 and v8 each have their own set of database tables. In case you want to remove your v5 data from the database you can safely delete all tables starting with
acymailing as these belong to v5. The tables starting with
acymbelong to v8.
As an important note for your upgrade to Joomla 5, please deactivate all Acymailing plugins and components and enable them again when you have upgraded to Joomla 5.