Copy-paste assets from Sketch App to Framer.
High-fidelity Prototyping with Framer
Raitis Linde

Sketch is actually capable of doing this. If you drag and drop a layer from the layer inspector, Sketch exports a PNG. This works on OS level so you can drag it into your Finder but also any application that works with PNGs. Therefore you can drag and drop a layer from Sketch instantly into Framer Studio. Works pretty sweet!