You can use a custom function on your functions.php file that will not affect your page speed and will allow you to modify the date format displayed when hovering over a post on the feed. To do so, please add the following to your functions.php file.
function sbi_custom_date ($timestamp) {
$timestamp = strtotime($timestamp);
$posted_on_date_str = ucfirst( date_i18n( 'M j Y', $timestamp ) ); // ex. Feb 2 2020
return $posted_on_date_str;
}
add_filter( 'sbi_posted_on_date', 'sbi_custom_date', 10, 1 );
You can modify the code and adjust the format to your needs; for more details, please check this article from WordPress Customize date and time format – WordPress.org.
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