welcome to Kentico community.
As you probably noticed you cannot use default repeater with custom query. However there are few options how to achieve your goal.
- you can override selectall query and still use you default repeater. But be aware that selectall query is used by default. If you need to list data always this way, it can be fine.
- you use Repeater with custom query. Then instead of using selected item transformation you link to the detail page with normal "a href" inside list transformation. The detail page will contain Universal Page Viewer webpart with your item transformation. Please note that detail page needs to stop inheriting list page template.
- you extend repeater with custom query. A bit old article, but principle is the same.
- you place two webparts at the list page (repeater and page viewer) and switch visibility based on the query string.