My Pipenv Setup

pipenv.md

In .bashrc

export PIPENV_VENV_IN_PROJECT=1
export PIPENV_IGNORE_VIRTUALENVS=1

In vscode project
pipenv --python 3.6 (or whatever version)
pipenv shell (vscode and pipenv should know where the .venv folder is)
pipenv install ...

Feels more like a node proj, but the point is that both vscode and pipenv know where my virtualenv is, and pipenv correctly installs things (when in the shell).

btw...
pipenv shell
pipenv install flake8

Then in (user) settings.json...

{
    "python.linting.pylintEnabled": false,
    "python.linting.flake8Enabled": true,
    "python.linting.flake8Path": "${workspaceFolder}/.venv/bin/flake8",
}

and with the setup above, those user settings shouldn't change across workspaces