Vat Exclude change text

apply_filters('tzn_tax_legal_info', $tax_legal_info, ['context' => $is_mini_cart]);

so if you need to change the text for the mini cart only, you can check the argument and do your stuff
$is_mini_cart is true as the name says in the mini-cart only

'context' => $is_mini_cart

add_filter('tzn_tax_legal_info', 'tzn_change_legal_info',99,99);
function tzn_change_legal_info($args['context'] = true){
   return 'exkl. Mwst';
}

-------
add_filter('tzn_tax_legal_info', 'tzn_change_legal_info',99,99);
function tzn_change_legal_info(){
   return 'exkl. MwSt.';
}

function adjust_vat_shipping_text($text) {
    $text =  '' . __('(exkl. MwSt.)', 'tzn') . '';
    return $text;
}
add_filter('tzn_cart_total_text', 'adjust_vat_shipping_text')