Ttdfjt

I want to change State/Province label. How can I do it?

Hope it's helpful

Way 1 :
If you want to change the shipping address fields as well as billing address fields, You can do via theme transaction if you have made a custom theme as per your language.

i.e: en_US

Way 2:
If you change made in shipping address fields only, Please override LayoutProcessor.php

Step 1 di.xml

path: app/code/vendor/module_name/etc

<?xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:ObjectManager/etc/config.xsd">
 <type name="MagentoCheckoutBlockCheckoutLayoutProcessor">
 <plugin name="Custom_Checkout" type="AmeexFasBlockLayoutProcessor" sortOrder="100"/>
 </type> 
</config>

Step 2:
LayoutProcessor.php

path:app/code/vendor/module_name/Block/

 public function afterProcess(
 MagentoCheckoutBlockCheckoutLayoutProcessor $subject,
 array $jsLayout
 ) 
 $jsLayout['components']['checkout']['children']['steps']['children']['shipping-step']
 ['children']['shippingAddress']['children']['shipping-address-fieldset']['children']['lastname']['label'] = __('Recipient lastname'); 

 $jsLayout['components']['checkout']['children']['steps']['children']['shipping-step']
 ['children']['shippingAddress']['children']['shipping-address-fieldset']['children']['region_id']['label'] = __('Division'); 

 return $jsLayout;
 
}

It's work like charm

According to this topic How do you edit checkout field labels in Magento 2? (sorry, wouldn't let me post as comment)

Translation for State/Province and Zip/Postal Code is found (by
default) in /vendor/magento/module-checkout/i18n directory.

You can copy locale's csv file from
/vendor/magento/module-checkout/i18n folder to
app/code/Magento/module-checkout/i18n directory.

Then find the text and change its translation.

After saving file, don't forget to remove content from /var/cache
folder and /var/page_cache folder.

You can overwrite below function for changing the Label at cart page in the file: vendor/magento/module-checkout/Block/Cart/LayoutProcessor.php

public function process($jsLayout)
 
 $elements = [
 'city' => [
 'visible' => $this->isCityActive(),
 'formElement' => 'input',
 'label' => __('City'),
 'value' => null
 ],
 'country_id' => [
 'visible' => true,
 'formElement' => 'select',
 'label' => __('Country'),
 'options' => [],
 'value' => null
 ],
 'region_id' => [
 'visible' => true,
 'formElement' => 'select',
 'label' => __('State/Province'),
 'options' => [],
 'value' => null
 ],
 'postcode' => [
 'visible' => true,
 'formElement' => 'input',
 'label' => __('Zip/Postal Code'),
 'value' => null
 ]
 ];

 if (!isset($jsLayout['components']['checkoutProvider']['dictionaries'])) 
 $jsLayout['components']['checkoutProvider']['dictionaries'] = [
 'country_id' => $this->countryCollection->loadByStore()->toOptionArray(),
 'region_id' => $this->regionCollection->addAllowedCountriesFilter()->toOptionArray(),
 ];
 

 if (isset($jsLayout['components']['block-summary']['children']['block-shipping']['children']
 ['address-fieldsets']['children'])
 ) 
 $fieldSetPointer = &$jsLayout['components']['block-summary']['children']['block-shipping']
 ['children']['address-fieldsets']['children'];
 $fieldSetPointer = $this->merger->merge($elements, 'checkoutProvider', 'shippingAddress', $fieldSetPointer);
 $fieldSetPointer['region_id']['config']['skipValidation'] = true;
 
 return $jsLayout;