🚀 go-pugleaf

If you mean you want to add what appears to be script linework on the IRS signature line so it looks like you've personally signed it, I'd do this. I'd "print" the IRS form using a free PDF printer such as the one included with PDFill to make a pdf of the 1040. Then, you and spouse sign a blank paper with names an appropriate distance apart to match the form. Scan the names and save as jpg or other format. Use a free program such as PDFill and use their merge tool to add the signature image to the IRS pdf as a watermark below the IRS pdf. You can size the image by percent and locate from edges by inches, so can move the signatures so they appear to be as if signed on the form. If you want a true security style "digital signature" where there is a binary code security system to prove your identity and prevent document changes, that's another whole issue. Somebody else can answer that one.