Note: You can also use the 'Overflow for Figma' plugin while in Figma, as explained here.
To insert your Figma frames in Overflow while being in the Overflow app, just use the Insert menu or the shortcut SHIFT + F.
The first time, you'll need to link your Figma account to Overflow. You'll be prompted to sign in to your Figma account and then to 'Allow Access' for Overflow to read your files.
You'll then be prompted to enter the link of your Figma file and optionally select export size (i.e. the pixel density you want to export your screens to; the default is 1x) or to include prototyping links. You can get the link from the address bar if using Figma in the browser or by copying the link from within the Share window.
Once the file has loaded, you’ll see the Figma Frame Picker. This is an easy way to filter and select which Frames from a specific Page you want to insert or replace in Overflow.
Frames can be inserted into any Board in any Document. Simply navigate to the Document/Board you like and hit Insert in the picker window when your selection is finalized. Re-syncing over a populated Board will replace Screens with the same name, updating all layers while keeping connectors intact.
You can manage this integration from Overflow > Preferences > Integrations.