Hi, with Resolve 8.0 now reading FCP7 XMLs that include cross fades you should be able to send the XML, have the source clips graded and hav resolve send the XML back to FCP7. In Resolve the colorist can see the clips in unmix mode so the crossfade does not affect the grade. That being said it’s also been common in the past to export clips with handles especially if the facility editing is different to the facility grading. This way if the edit changes after the grade, you have a few frames/seconds either side of the original edit already graded.
Peter