Are there any websites/software that support VR video playback with local video/script files?

Something similar to the old syncydink where you could play local video/scripts and it had VR video support.

MPV/MultiFunPlayer combo is pretty legit

You can just use Whirligig as a VR player. There are several programs that control toys via scripts which will utilize the time code that Whirligig can be configured to publish on the local network.

More specific advice would require knowing what hardware you’re trying to use.