Hello! In the week of August 2nd, the link for "Gehitu loturak/Aldatu loturak" will be restored to the sidebar. It will appear in the Tresnak section as "Hizkuntzen arteko loturak gehitu/Aldatu hizkuntzen arteko loturak".
When building the language button, we did not include the "Gehitu loturak/Aldatu loturak" link. This was because this functionality is a part of improved language selector. That selector is currently being built by another team of the Wikimedia Foundation. As a result, the link was missing. We have received requests to restore it.
We explored the best way to do it as a temporary solution. We decided to add it into the sidebar in the Tresnak section. You can see the location on the screenshot.
When the improved language selector is deployed, the "Gehitu loturak/Aldatu loturak" link will be back together with the language links in the button.