How to do the translation of the .po files in child theme
Step1: Install the WpRentals Theme – https://help.wprentals.org/article/theme-installation/
Step2: Download the “All files & Documentation” from your buyer account. Unzip and find the wprentals-child-po.zip file
Step3: Upload the child theme and activate it. Set the WordPress language in Settings
Step4: Edit the po files inside the child theme with poedit and upload them in wprentals-child-po/languages via FTP or upload Loco Translate plugin and edit the .po via wp-admin interface. Save the edits.
You may need to sync your translation po and mo with the new theme updates.