1. That's very misleading, because what PyCharm did was add support for jupyter notebooks. Without iPython/Jupyter there would be no "interactivity and cell based execution" in PyCharm.
2. And AFAIK it's just Python, does it support the few dozens other jupyter kernels?
1. No, it's not. In regular python files you can create cells using #%% and run them separately. Yes, there is also notebook support but it requires Jupyter.
2. And AFAIK it's just Python, does it support the few dozens other jupyter kernels?