1.) Deactivate and consolidate plugin on dev.
2.) Deactivate and consolidate plugin on staging.
3.) Deactivate and consolidate plugin on live.
4.) After week of deactivation and consolidation on live, given no issue/s occur related to the plugin. Create a backup of the plugin file copy, store on FoF google drive then delete plugin files on dev and staging manually via ftp.
5.) Monitor dev and staging for any issues related to the plugin files for 3 weeks that could have caused by deleting the plugin files.
6.) After 3 weeks of deletion of the plugin files on dev and staging. Backup plugin file copy from live, store on FoF google drive then delete plugin files on live manually via ftp.
7.) After week of deletion of the plugin files, create a report that the plugin was successfully consolidated without any issue/s.
That's all!