I use different email accounts to write in multiple languages, each account with it’s own language. It would be very helpful to have spellcheck language as a per account option. After all, the email providers already have this option built in when using their respective web based interfaces. Thank you.
In webmail you can’t have more than one account open in the same window and have separate languages for each folder. You have to switch accounts to change the language. What eM Client does is have them open in the same window in separate folders. You can switch languages on the fly in Menu > Tools > Spell Check Languages, if that helps.
I would be interested to know if there is a webmail provider who does offer separate languages per folder, as I have not seen that before.
I don’t know about other email clients, but I would be more productive if every-time I write an email the language would be automatically selected for the account I am using. I believe is a reasonable request and relatively straightforward to implement. I hope you consider it.