LAUNCHXL-CC26X2R1: Is there guide for on-chip OAD porting to Multirole project?

I did read that section. but that section did not include about on-chip guide.

As I known, there is no dedicated guide for adding on-chip OAD to multi-role example but the steps are similar. You can try to combine the steps in "Add OAD to Multi Role" and simple_peripheral_oad_onchip example to make it.