Getting Plugins to cortex from 3rd party companies in one of the following versions: VST, VST3, Audio Units, AAX Native or AudioSuite formats.
I think that will never happen 
I agree with you, that would be an awesome thing for various purposes. In my opinion, Neural DSP is not interested in this feature. This would be like Apple implementing something like Java applications. They would completely lose control of what the user can install on the QC and badly coded plugins would lead to a lot more support requests. That is too much risk.
If I recall correctly, NDSP announced some time ago that they have plans on implementing a capture functionality for effects.
That would be a substitution for direct plugin support.
As far as I know this fx capture is not possible on any device yet, so it will probably be a while until we get this.