How to collaborate/ Remotely work with your team in after effect with data security ?

Way before the internet I worked on a lot of projects that had very sensitive original footage. We got workprints that were watermarked with a burned-in overlay that said Property Of ~~ and Do Not distribute or similar warnings. We signed extremely binding NDA's with very big financial penalties, some of the penalties were almost equal to the cost of a new home. The NDA is the strongest defense you have to members of your team releasing proprietary materials. There is little or nothing you can do about folks stealing your property except being very careful. There is not very much you can do to guarantee that someone that wants to hack your system can't get it done. 

The only thing you can do to protect the original footage is to send your team watermarked low-resolution proxies of the footage. The footage AE uses has to be on a local or network drive. I don't know of any professional editing app that can dynamically access a video stream in real-time from the internet. 

Pay a lawyer to draw up a legally enforceable NDA with significant financial penalties for any unauthorized disclosures, and set up your master AEP files with Proxies for the footage and share the proxies. I'm on a project using HD watermarked proxies right now for a 4K project. I don't rely on full-resolution previews anyway so working with proxy footage has very little effect on my workflow. 

Depending on how much editablity you're looking for, the best you can do with actual project files is something like an exported .mogrt file. A Premiere user could access certain controls that you have revealed, but not have access* to the rest of the project. (It should be noted that someone who knows how can still access the original AE File, though.)

There are also cloud-rendering solutions with a similar approach, where you could expose a handful of controls to a web-facing interface, and those control various editable properties in a templated After Effects file. The end user would have limited controls, but would never touch the AE file itself.

Here are some options, if that approach is viable for you: 
https://dataclay.com/templater/
https://simplate.io/
https://www.cloneless.com/ 

There is no such thing even in Adobe Anywhere/ Teams. All work is always based on local copies of iles that are synced after the fact, not live editing some file in the cloud. It's also beside the point. Adobe can't take your responsibilities off your shoulders and if you can't trust your employees/ collaborators/ team members, you need to find different ones.

Mylenium