I have tried numerous times, checked and re-checked GMail settings, but I cannot get Junk E-Mail to sync with GMail/Spam.
When I clear Junk E-Mail in eMClient, the emails remain in Gmail/Spam.
I don’t even see Junk E-Mail label in Gmail settings
Junk E-mail is the eM Client term for Gmail’s Spam. It should be the same folder.
Go to Menu > Accounts and click on the Gmail account’s IMAP tab.
Special folder names should be automatically selected, but if not tick that and see if it makes any difference.
In this example you can see that the Gmail Spam folder is mapped to eM Client’s Junk folder. That should be the default setting.