Where to put localization (*.po) files when using src-layout?

[buhtz]

Imagine a project folder layout like this with one Distribution Package having two import packages.

bit_demo
├── pyproject.toml
├── src
│   ├── bitcli
│   │   ├── __init__.py
│   │   └── __main__.py
│   └── bitgui
│       ├── __init__.py
│       └── __main__.py
└── tests
    ├── ...

Where should I create the locale folder containing the *.pol files?

In context of setuptools I assume this files are "data files" and should treated like that in the pyproject.toml, right?

I'm not sure if I should separate the locale files for the two packages bitcli and bitgui. I'm free here in the decision. I assume it is better two share only one locale folder for the whole Distribution Package used by both import packages?