DaVinci Resolve does not allow plug-ins running in its Edit page to provide drop zones or similar user interface elements that allow users to specify additional video inputs for a plugin.
To overcome this limitation, plug-ins display a button that allows you to select a video or image file anywhere on your system.
Clip or photo selection button
When selecting a video clip, please note that the clip is played back from beginning to end. It is not currently possible to trim and select a specific range of frames to be used.