There needs to be a clear distinction made here between an electronic signature, which is essentially embedding a scanned copy of someone's signature into a PDF at a specific location, and a digital signature, which has no "looks like a person's real signature" component at all but is generally legally binding.
I've just gone through trying to add both with Adobe Reader DC and have to report that I can find no way to do either with a screen reader. Adobe has made a massive step back in accessibility with Reader DC. I must admit, though, that I did not try NVDA's object navigation to try to get to the controls, and that at least has the potential to work, but may not, either.
If you are actually the signatory and want an electronic signature, then I'd strongly suggest that you set up the template you use to create the review in the first place such that your electronic signature is already in it. If you have control over the electronic copy of the template, as well as the documents generated from it, this is a workable solution.
Brian - Windows 10 Home, 64-Bit, Version 1809, Build 17763
Explanations exist; they have existed for all time; there is always a well-known solution to every human problem — neat, plausible, and wrong.
~ H.L. Mencken, AKA The Sage of Baltimore