You will still need internet access on another server to download the package.
From the server that has access to internet.
pip3 download mysql-connector -d "./mysql-connector"
tar cvfz mysql-connector.tar.gz mysql-connector
Transfer the mysql-connector.tar.gz to the target server
On the target server where you want to install the mysql-connector
tar zxvf mysql-connector.tar.gz
pip3 install * -f ./ --no-index