Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/stm32/stm32wb0/STM32WB07/RADIO/ANTSW3_DIG_USR#0x0
ANTSW3_DIG_USR register
specifies the exact timing of the antenna switching during transmission at LE_2M baud rate (in AoD).
https://github.com/modm-io/cmsis-svd-stm32