Is it possible to add initials to a Journey task, rather than a full signature?

Summary:

We are creating a journey for a policy that is required for some of our campus to complete annually. Because of the link of the policy, I'm creating a new task for each section of the policy. I currently have each task an electronic signature, using last name validation. I'm wondering if it's possible to do a similar thing, except with initials rather than last name.

Content (required):

n/a

Version (include the version you are using, if applicable):

23C

Code Snippet (add any code snippets that support your topic, if applicable):