WP + TinyMCE + Color Picker Plugin + Text Color Plugin = ❤️

functions.php

<?php

if ( ! function_exists( 'thistle_remove_tiny_mce_colorpicker' ) ) {
    /**
     * Pulls out the colorpicker plugin from TinyMCE.
     * Without this plugin the end user cannot select a custom color.
     *
     * @link https://www.tinymce.com/docs/plugins/colorpicker/
     *
     * @param array $plugins An array of default TinyMCE plugins.
     * @return array
     */
    function thistle_remove_tiny_mce_colorpicker( $plugins ) {
        return array_diff( $plugins, array( 'colorpicker' ) );
    }
}
add_filter( 'tiny_mce_plugins', 'thistle_remove_tiny_mce_colorpicker' );

if ( ! function_exists( 'thistle_tiny_mce_textcolor_map' ) ) {
    /**
     * Specifies a map of the text colors that will appear in the grid of
     * the textcolor plugin.
     * If the map is empty, the textcolor plugin is pulled out.
     *
     * @link https://www.tinymce.com/docs/plugins/textcolor/#textcolor_map
     *
     * @param $mceInit array An array with TinyMCE config.
     * @return array
     */
    function thistle_tiny_mce_textcolor_map( $mceInit ) {
        $textcolor_map = apply_filters( 'thistle_tiny_mce_textcolor_map', array() );
        
        if ( ! empty( $textcolor_map ) ) {
            $mceInit['textcolor_map'] = wp_json_encode( $textcolor_map );
        } else {
            $mceInit['plugins'] = explode( ',' , $mceInit['plugins'] );
            $mceInit['plugins'] = array_diff( $mceInit['plugins'], array( 'textcolor' ) );
            $mceInit['plugins'] = implode( ',' , $mceInit['plugins'] );
        }
        return $mceInit;
    }
}
add_filter( 'tiny_mce_before_init', 'thistle_tiny_mce_textcolor_map' );