How to set a custom colour pallet for ACF's colour picker field. For more info see https://philkurth.com.au/tips/how-to-customize-the-colour-palette-for-acfs-colour-picker-field/

customising-acf-colour-picker-field-pallet.php

<?php

add_action( 'admin_footer', function () {
	?>
    	<script>
	    if (window.acf) {
	        acf.addFilter('color_picker_args', function (args, $field) {

		    args.palettes = [
		        '#E6D8D5',
		        '#E75274',
		        '#F9FEFD',
		        '#58C2B5',
		    ];

		    return args;
	        });
	    }
    	</script>
	<?php
} );