If the tool requires you to disable your antivirus or run a "keygen," it is malware. Period.
Most reputable e-signature platforms (DocuSign, PandaDoc, Adobe Sign) operate on a "Freemium" model. They allow you to sign for free, but if you send a document to someone else to sign, the finished document often contains a "patch" or watermark (e.g., "Created by DocuSign") unless you pay. esign patch free
If you were referring to bypassing payment for commercial software: If the tool requires you to disable your