I added the following to /home/pquarato/.bashrc:

export PYTHONPATH="/home/bli/.local/lib/python3.6/site-packages" 

This seems to solve both issues (ModuleNotFoundError and DistributionNotFound).

The .bashrc file needs to be sourced before this takes effect.

This probably needs to be adapted depending on the shell that the user uses.

I added the following to /home/pquarato/.bashrc:

export PYTHONPATH="/home/bli/.local/lib/python3.6/site-packages" 

This seems to solve both issues (ModuleNotFoundError and DistributionNotFound).

The .bashrc file needs to be sourced before this takes effect.

This probably needs to be adapted depending on the shell that the user uses.

Edit

Setting PYTHONPATH doesn't seem to work with local packages that were installed as *.egg-link using pip3.6 install -e. In such cases, there is still a ModuleNotFoundError.