Open login page by Ctrl+Alt+L. Can be used as a mu-plugin.

kagg-shortcuts.php

<?php

/**
 * Add shortcuts.
 *
 * @return void
 */
function kagg_shortcuts() {
	?>
	<script>
		window.addEventListener( 'keydown', function( event ) {
			if ( event.ctrlKey && event.altKey && event.code === 'KeyL' ) {
				window.location.href = '/wp-login.php';
			}
		} );
	</script>
	<?php
}

add_action( 'wp_print_footer_scripts', 'kagg_shortcuts' );