Hi Emmanuel,
No there is not an application note for the FCCU on S32G2. The main sources of information on the FCCU are: the FCCU chapter in the S32G2 RM, the Fault Map attachment to the RM (including the notes at the foot of the page) and the S32G2 safety manual.
Please let us know if there is a specific aspect of the FCCU that is not clear.
Many thanks,
Alison