Can you recommend an email client with label synchronization and flexible spam settings, preferably cross-platform?

Question

Email

Thunderbird is not bad in principle, except that I didn’t find how to send mail to spam by keyword (is this even possible?) and didn’t find label synchronization (I created a login label on my computer, marked the necessary letters, but this remains only on the client side, on another thunderbird has to do the same).
Can you suggest?

Answer 1

there are none
, but nothing prevents you from synchronizing the config, through the same Dropbox, for example