Hello,
Yes of course, you are free to use your preferred language plugin to add a custom PO/MO language file for Serbian. Our plugin follows the WordPress standards to load the proper language files for the currently active language of your website, and of course any existing language translation string could be overridden through the Gettext native functions.
We also support any page-builder plugin by declaring all the available widgets and shortcodes that you can publish through your preferred plugin. Just remember to not use the Shortcodes on the homepage but rather the Widgets. For any other page of your website, except the home page, you can use either Shortcodes, Widgets or both.
We invite you to test all these functions by installing Vik Rent Car on any existing WordPress website.
The VikWP Team
