Different error message for first and last name

Hello,

[I first mistakenly posted this question in the wrong forum. Sorry for double-posting, it was an error…]
I am using the default “Name” field with the “Firstname, last name” format. Problem is the validation error message (in case of empty field) is the same for both fields: “Your name is required.”
Is there a way to use two different message (“Your first* name is required” and “Your *last* name is required”) ?

Just in case: using a dedicated new field for the first name is not an option because it would not show in the email “From: ” field (and I need both first and last name here).

Thanks for any help!

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