I am curious why the secondary Touch Shortcut is blank for the pixel brush? Erase and colopicker are a common pair that is not available to fresco because of the non-functioning secondary touch. PS for iPad has the same Touch shortcut UI and it allows both.
This is a great question, possibly something that the development team overlooked and just never revisited.
Comparing one Adobe app with another - completely different teams work on each app as far as I've been able to tell, so just because it's in one app doesn't automatically mean a feature will appear across the board.
I would suggest heading over the the Fresco UserVoice page and making a request that the secondary touch shortcut option be givent to us in Fresco as well.
Through the app you can go to App Settings > Help > Suggest a feature. This will open up the Fresco UserVoice page in your browser.
Exactly. It may have different functionality, but the team used it, because they wanted to have a consistent UI among the mobile apps for ease of use