I think I found the answer, there are a couple of options that I can include in the tfsec:
--custom-check-dir string Explicitly set the custom checks dir location
--custom-check-url string Download a custom check file from a remote location. Must be json or yaml

Can I use the option --custom-check-url and generate different rule files in the URL?
for example.... tfsec --custom-check-url https://github.com/Jackson-National/tfsec-custom-rules/blob/main/.tfsec/