You want to deploy FIPS enabled ISG proxy with ZTP without human intervention.
Deploying a FIPs enabled ISG/EdgeSWG proxy with ZTP is not supported and it is not in the focus area of the current road map as of this writing.
An alternative is to deploy regular (non-FIPS mode) ISG/EdgeSWG proxy via ZTP and enable FIPS mode manually or through executing scripts on Management Center to all deployed proxy.