Ignition is not FIPS 140 validated and does not run on a FIPS enforced host. Inductive Automation has not committed to FIPS validation or compliance.
Specifically, the Gateway will not start on a host with OS level FIPS mode enabled (for example RHEL in FIPS mode) because internal components use algorithms that FIPS mode removes from the Java provider, such as SHA1PRNG for secure random. There is no configuration setting that changes this.
What you can control: the TLS ciphers and protocols the Gateway web server offers, under Web Server Settings. That covers browser and client connections, which is where most audit findings land. Cryptography used elsewhere in the product (OPC UA, Gateway Network, internal secrets) is not configurable.
If FIPS is a hard requirement for your deployment, reply here, post to ideas, and/or contact your account representative so we can record the need.
Related posts: Ignition Cryptography Algorithms (original question, RHEL FIPS mode), Web Server Settings: cipher support, Updating Java in Ignition.