I use gmail, and have recently become enamored with Google Apps scripts. I have a couple that create the Omnifocus url schemes with action name, project, tags, due & defer dates, the link to the email in notes (along with whatever else based on the email, write them to a shell script that gets put into a google drive folder. Hazel sees the file, renames it and kicks off a shell script that changes the permissions and executes the file, opening each url.
The added bonus is that the apps scripts are server side on gmail, execute every x minutes or hours, and can use various parameters to send to OF. You can build tasks off labels created by filters (rules), then change the labels. You can set dates, tags, etc based on parsed content from the email. I also have scripts that have run based on manually applied labels like OF Tomorrow or OF Next Week. Since it runs server side at gmail, it works from any gmail client. If your Mac isn’t running, it will catch up when it is, or you could run a workflow in Shortcuts.