How to override function "ValidateAddress()" in /wp-includes/class-phpmailer.php

Hello!

I am running a member site by WP,
and I’ve found that lost-password-retrieve function does not work with RFC-invalid-email-address which some users are using.

I cannot force them to change their email addresses,
so now I seem to have to make a change to the function “ValidateAddress()” in /wp-includes/class-phpmailer.php to loosen the regex pattern for them.

Is there any way to do it without changing the core file directory?

Thank you 4 your patience to my broken English,
and many thanks in advance!