This thread is resolved. Here is a description of the problem and solution.
Problem: we are publishing an identical post on two different translated websites. I want to add a canonical tag on the duplicated post that points to the original version. How do I handle hreflang in this situation?
Solution: WPML adds automatically canonical URLs to duplicated content so that Google does not mark them as copied content. You can use a canonical URL in your second site to point to the first one - this should solve the problem and you can easily do it with Yoast, for example, that is WPML compatible. About hreflangs, it's not possible to remove them or Google won't know in which language the page is written, but this shouldn't cause any issue with the rankings. But pointing the canonical URL to the first site you should avoid any problem.
This is the technical support forum for WPML - the multilingual WordPress plugin.
Everyone can read, but only WPML clients can post here. WPML team is replying on the forum 6 days per week, 22 hours per day.