Hi,
Thank you so much for your interest in our products and for using our community.
For the ADC, in VLPR and STOP1 modes the module and clock sources are completely disable. And using ADC, you only can wake-up the MCU through a sync interrupt in STOP2.
For more reference you can consult the Table 39-4. Module operation in available power modes and Table 7-8. AWIC stop and VLPS wake-up sources from reference manual.
Hope it helps you.
Have a nice day!