Drupal 8: Node preview when using Page Manager
Not ouf the box because page_manager is about routes, and node preview is a completely different route than viewing a node.

Something like Display suite and probably also Panelizer (never really used it myself) whould probably work there though.

That said, it should be possible to build something too with Page Manager too by creating a second page (with a duplicated page variant(s) that you need to keep in sync somehow) that overides the preview route, but you also need to somehow write a context provider that loads the node based on the passed tempstore argument and also a write a block that replicates the UI elements for selecting the view mode and going back to edit