Can the rating provided by worker from self-evaluation be used as their Overall Performance Rating?

Summary:

We have a requirement for a subset of our client's employees to where the worker themself is tasked to self-evaluate themselves with their annual performance document (including providing their own ratings and scores).

Since Manager Evaluation of Worker is not part of their evaluation- is it possible to derive the ratings provided within the worker self-evaluation to be used as their Overall Performance Rating/feed into their Talent Score? If so, are there any other steps that we can be sure it is done so? (Talent Review considerations, etc.)

Or can this option be captured only if the line manager enters ratings and provides it?