syncing local email folders across Mac devices

As an example and works very well for my setup across two M1 Apple Computers running Monterey macOS 12.4, one Apple Desktop running High Sierra macOS 10.13 and one iPhone running iOS 15.5

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Q - " syncing local email folders across Mac devices "

A- By virtue of Local e-email folders, this implies the e-mail folder are not stored on a Cloud Service which uses the IMAP Protocol ?

A - Therefore, the folders are Stored Locally as on the Internal Drive of this computer ?

Welcome for being helpful in pointing the right direction