Simple validation rules using rule editor

We are working in a headless setup and i am trying to stay away from writing any custom JS functions for form field validations due to security reasons.

For a simple rule example, prevent a Name field from accepting any special chars, i am unable to accomplish this entirely with rule editor. Tried many combinations and none worked. Have few similar use cases, where i need to use rule editor. i tried using “contains” but unable to find a way to concat multiple special chars.

Any rule that i can pass a regex to validate, example Account Number (custom xx-xxxxxx). In foundation, we used to have a way to pass Regex. In core, i only see few OOTB example SSN, Phone number, Email, Zip etc.