I'm not sure what you are talking about. It will be installed in the virtual environment just the same. There is no mechanism for it to "only be visible inside other packages configured with poetry".
There is a standardized API for package tools to expose and invoke editable-install functionality [1] which pip install follows, but Poetry didn't implement this API before (I see it does now though as of this past February [2]).
In other words, this a more thorough explanation of my point from [3]:
> Yes, if you ran poetry install you could get editable mode, but that requires every single end user of your package to install poetry and explicitly invoke a poetry install just for your package. And if someone else's package uses a different package builder, now they need to install and invoke that one. And on and on, and you end up with a six-hundred-line install script because of all the one-off "must install this developer's favorite package manager to use their package" stuff.
