Yes, iMovie, as of v10, is effectively "Final Cut Express," as the 'reduced' Final Cut was called in legacy versions. It uses the exact same elements, such as titles, generators, effects, etc., as Final Cut Pro does, and it is identical under the hood as well. This is why you can send your project directly to Final Cut Pro with just a click of the respective menu command without losing even the tiniest percent in translation. Unlike every other NLE. For example, LumaFusion has to go via XML. Something that will be lossy 9 out of 10 times. Keyboard shortcuts for identical commands are also identical.
The same goes for iMovie and Final Cut Pro for iPad, btw.