How to translate Dutch to German without English as a middle language

Fatal error: Uncaught TypeError: call_user_func_array(): Argument #1 ($callback) must be a valid callback, function "udesign_single_post_imagei_child" not found or invalid function name in /home/noborderstransla/public_html/wp-includes/class-wp-hook.php:310 Stack trace: #0 /home/noborderstransla/public_html/wp-includes/class-wp-hook.php(334): WP_Hook->apply_filters('', Array) #1 /home/noborderstransla/public_html/wp-includes/plugin.php(517): WP_Hook->do_action(Array) #2 /home/noborderstransla/public_html/wp-content/themes/u-design/lib/u-design-hooks/u-design-theme-hooks.php(390): do_action('udesign_single_...') #3 /home/noborderstransla/public_html/wp-content/themes/u-child/single.php(32): udesign_single_post_entry_top() #4 /home/noborderstransla/public_html/wp-includes/template-loader.php(113): include('/home/noborders...') #5 /home/noborderstransla/public_html/wp-blog-header.php(19): require_once('/home/noborders...') #6 /home/noborderstransla/public_html/index.php(17): require('/home/noborders...') #7 {main} thrown in /home/noborderstransla/public_html/wp-includes/class-wp-hook.php on line 310