Magento 2 Swatches changes the default error notice for product views. Instead of showing default error notice, it will show customize notice which suitable for each attribute.
Before you continue, ensure you meet that you have installed Magento2
Run the following commands in Magento 2 root folder:
composer require magepow/swatches
php bin/magento setup:upgrade
php bin/magento setup:static-content:deploy -f
If this project help you reduce time to develop, you can give me a cup of coffee :)