No. Images and attachments in cold email hurt on every axis: they trip spam filters (unknown sender + attachment is a phishing signature), break the one-human-to-another illusion, and add load time to a message that gets three seconds of attention.
Plain text, or minimally formatted HTML that LOOKS like plain text, is the professional standard for outreach, and it consistently outperforms designed emails on deliverability and replies. Your signature can carry one link; the body carries words.
Have something visual to show? Link to it ('two-minute demo here') so the interested click and the filters stay calm. Attachments come after they reply.