The IDX page template will take the global header setting you apply in Theme Options (see global header setting) and use the default sidebar position and type (Primary Sidebar, Right Position). You can use this template if you activate a third party IDX plugin, such as dsIDXPress or iHomefinder. The theme design, search and shortcodes will NOT apply to IDX plugins data.
If you wish to integrate MLS and use the theme property page with all the design options as in our demos, you must import properties.
The simples solution to import MLS listings in WPResidence is MLS Import, a 3rd party fully compatible plugin. This application does automatic data synchronization, adds, updates and deletes expired listings hourly. It serves images from MLS CDN directly. Check more on their website https://mlsimport.com/
Ex of IDX page from dsIDXpress with Global Header -> None.
Ex of IDX Property page added with MLS Import plugin