The best way to back up your Yahoo emails is by using the MacSonik Yahoo Backup Tool. You can choose the folders you want and back up specific emails using a date filter. This tool exports Yahoo Mail to PST, MBOX, and MSG. It has a simple and easy-to-use interface, so anyone can use it without technical skills. A free trial version is also available to try first.

To Know More: https://www.macsonik.com/yahoo/backup/