configuration of I2c mode SMBus is not supported on STM32CubeMX 5.1.0 so how can i do it manually ?

[Karou]

[Piranha]

Maybe exactly like every other peripheral - with reading reference manual and writing register values?

[asbjorn.heid]

Just doing a quick search, the LL library seems to have some SMBus support, at least for the F1 series.