Ah! The problem you seem to be facing is you can't create virtualenv with python3.

And to install dependencies for python3 environment you run pip3 install package-name

Follow these steps for creating virtualenv in python3 environment:

virtualenv -p /usr/bin/python3 yourenv
source yourenv/bin/activate
pip3 install mysql-connector

To install the official MySQL Connector for Python, please use the name mysql-connector-python:

pip install mysql-connector-python

Some further discussion, when we pip search for mysql-connector at this time (Nov, 2018), the most related results shown as follow:

$ pip search mysql-connector | grep ^mysql-connector
mysql-connector (2.1.6)                  - MySQL driver written in Python
mysql-connector-python (8.0.13)          - MySQL driver written in Python
mysql-connector-repackaged (0.3.1)       - MySQL driver written in Python
mysql-connector-async-dd (2.0.2)         - mysql async connection
mysql-connector-python-rf (2.2.2)        - MySQL driver written in Python
mysql-connector-python-dd (2.0.2)        - MySQL driver written in Python

• mysql-connector (2.1.6) is provided on PyPI when MySQL didn't provide their official pip install on PyPI at beginning (which was inconvenient). But it is a fork, and is stopped updating, so

  pip install mysql-connector
  

  will install this obsolete version.

• And now mysql-connector-python (8.0.13) on PyPI is the official package maintained by MySQL, so this is the one we should install.