You could add an action trigger with a custom save MF. We use this construction a lot in projects. You commit the object in the MF and execute the logic that you initially wanted to link to the default save button.
MF looks like this:
Make sure you set the control bar to visible: false.
I should use an action trigger.
This triggers an microflow where the a change action (commit box : yes) can be set. The action trigger can be renamed or restyled in the theme so it looks like a save button.