Unfortunately, the feedback ADCs for high-side outputs from 8 to 10 are unusable on ADC_MA channels. This is a bug on FCE2.0 and is resolved in the next versions.
As a workaround for feedback for HSO9/10 ADC, you can use another ADC channel ID available on that pin(ADC1_S18). Just ensure the secondary channel ID is not being used on any other physical pin.
Unfortunately, there is no workaround for the feedback pin for HSO7/8.
Thanks,
Amir