Yes!
Another option is to disable bluetooth (dtoverlay=disable-bt), then the primary uart on /dev/serial0 changes from the mini-UART (ttyS0) to the PL011 UART (ttyAMA0) previously used for BT-HCI, which does work for stm32flash. So it's possible to get stm32flash working on the same pins without using another UART, if you can give up BT.
Support for Wireless Firmware updates on STM32WBxx
Have wireless update also flash the firmware
Make some error messages possible to disable
Add commands for FUS (wireless firmware) interaction
Add flag for chips with special wireless firmware update
Firmware Update Service (FUS) functions