If you want, since it'll be generated in an Air-Gap machine (offline), you can screenshot the window when the seed phrase is displayed.
It's not too fancy but it'll definitely be  "true to the UI's design".

For example:
Sparrow will display this when you click "View Seed..." button in the wallet's 'Settings' tab:


Electrum's look like this:


By default, those images will have a white background but you can change it like so by enabling "Dark Mode" in either wallet's settings.

But in case if you chose Electrum; you must include a note that the mnemonic should be restored to Electrum since it's not compatible with some bitcoin wallets.