They're called "wet signatures"

"However, many jurisdictions still require a wet signature. For instance, in the US and Canada, notarized documents require signatures in wet ink. Similarly, documents in areas such as family law, wills, trusts, or banking also require physical signatures. In the UK, tax authorities require a wet signature for any tax documents filed by a British resident."

https://www.adobe.com/acrobat/business/resources/wet-signatu...