The migration plugin https://wordpress.org/plugins/qtranslate-to-wpml-export/ is no longer under development nor supported and it became incompatible with WPML since 126.96.36.199.
A possible workaround is:
-Install WPML 188.8.131.52
-Migrate (do it with a minimal install, just the necessary plugins and a default WP theme)
You can get older versions of WPML here:
Ovdje se mogu skinuti i stare verzije WPML: https://wpml.org/account/downloads/ – click “Changelog” to download.
you need to be in LEGACY-mode, that is <–language–> not in [language:] – zapisi sa [language:] tagovima se neće prebaciti