Add line

Add this to your functions.php

add_filter( 'xoo_sl_social_buttons_el_popup', function( $html ){
		$html  = '<span class="xoo-sl-loginvia">'.__( 'or Login Using', 'social-login-woocommerce' ).'</span>';
		ob_start();
		xoo_sl_get_social_buttons(); //Get buttons HTML
		$html .= ob_get_clean();
		echo $html;
	} );