Reversing First and Last name

Hi there @wikvdw ????!

Thank you for reaching out to MailPoet Support!

I am going to send Newsletters to Japanese users, whose names should show up as
Last name, First Name in the “To:” section of the email.

Sure thing. Here you have a tutorial that explains how to customize newsletters with shortcodes (such as First and Last Name)

If you are sending to Japanese and non-Japanese users you might want to create different lists so that you can create two different templates with the first and last name in a different order: https://kb.mailpoet.com/article/282-create-a-list

I hope this helps!

Cheers!