Install the Ukrainian language pack via composer is never easier.
Install Ukrainian pack:
composer require qpard/magento2-ukrainian-language-pack:*
php bin/magento cache:clean
php bin/magento setup:static-content:deploy uk_UA
Update Ukrainian pack:
composer update qpard/magento2-ukrainian-language-pack:*
php bin/magento cache:clean
php bin/magento setup:static-content:deploy uk_UA