Note: the applicant's signature at the back of the visa form of each country must be consistent with the holder's signature, otherwise it may be refused by the embassy or even blacklisted.
Signature on passport:
When the border inspection authorities or immigration agencies can't determine whether your identity is consistent with your passport, they will determine it by comparing your signature, so as long as it is my signature, there is no problem. It is also useful when filling out entry and exit cards of other countries, such as entering Hong Kong.
In addition, in foreign countries, especially in European countries, signatures are basically recognized. If you have trouble spending money by credit card abroad, you can have vouchers.