Caracter non UTF8 with v7.2.1

How did you migrate ?
Did you backup / copy database ?
Did you install new code or overwrite existing ?

I did copy but restauration is ok to other instance database..

It may be source of issue.
If your server is not fully configured in UTF-8 (even if collation is utf8_general_ci) export / import may lead to incorrect charset.

Check directly in DB if characters are stored the same way as origin.
Attention, sometimes, your source is not correctly stored in UTF-8 (you'll see accentuated charactes like Ã.. with phphMyAdmin) and export / import set it the good way.
If it is the case add (or change) value for parameter enforceUTF8 in parameters.php.
If your DB is correctly stored in UTF-8,
$enforceUTF8 = '1';
in parameters.php should display correctly accentuated characters.
Otherwise, set
$enforceUTF8 = '0'; // Or remove the line
If accentuated characters are correctly displayed, it means your DB is not correctly configured.

Do you have SQL syntax for automatic update all é as é ?

There is no.

You must export DB.
Convert dump file.
Reimport.