This thread is resolved. Here is a description of the problem and solution.
Problem: How to use same slug in original pages and in translations
Solution: Yes, it's possible for pages/posts to have the same slug across languages.
For the custom page/post to have the same slug, go to WPML=>Settings => Translated documents options=> and select 2nd or 3rd option as per your need : https://take.ms/3TigH
After this option is saved now you can go to your secondary language post/page and within edit by the permalink you can click edit and edit the slug: https://www.wpbeginner.com/wp-tutorials/how-to-create-custom-permalinks-in-wordpress/ (check method 2 here)
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.