You can change only text which is written in translation

Like : $this->__("Sample Taxt");

Suggested text not written in translation so you can not change it with translation.

If you want to change it, you can find it in JS file which is located :

vendor/magento/module-checkout/view/frontend/web/js/model/shipping-rates-validator.js

Note : You have to override JS file to in your theme.

You can change only text which is written in translation

Like : $this->__("Sample Taxt");

Suggested text not written in translation so you can not change it with translation.

If you want to change it, you can find it in JS file which is located :

vendor/magento/module-checkout/view/frontend/web/js/model/shipping-rates-validator.js

Note : You have to override JS file to in your theme.

Delete pub/static/*

Run Command :

php bin/magento setup:static-content:deploy 

php bin/magento cache:clean

Delete browser cache.

Csv file path wrong which you have used.

frontend/..theme../Magento_Checkout/i18n/en_US.csv

Csv file should be located to given path.

app/design/frontend/YourTheme/ThemePackage/i18n/en_US.csv

Run Below command

php bin/magento cache:clean

You can change only text which is written in translation

Like : $this->__("Sample Taxt");

Suggested text not written in translation so you can not change it with translation.

If you want to change it, you can find it in JS file which is located :

vendor/magento/module-checkout/view/frontend/web/js/model/shipping-rates-validator.js

Note : You have to override JS file to in your theme.