leapcast VS miraclecast

Chromecast is completely closed-source, I'd argue against buying into that ecosystem.

Nymphcast [1] is an alternative, but wouldn't be compatible with existing clients, since the protocol is different.

Miraclecast [2] is an implementation of miracast/wi-fi display that runs on Linux. There is also a myriad of alternatives: vnc, raspicast, etc.

Leapcast [3] used to be an implementation of what you want (while using chrome as a black box).

There are some implementations of airplay.

[1]: http://nyanko.ws/product_nymphcast.php

[2]: https://github.com/albfan/miraclecast

[3]: https://github.com/dz0ny/leapcast

Running your own Google Cast receiver was blocked years ago: https://github.com/dz0ny/leapcast

Edit: maybe micraclecast might help but it seems a bit complex to set up. Seems it doesn't support connecting to external displays yet. So not very useful for this use case.

I tried running Miraclecast on the Linux device, but it requires me to stop the network manager, which isn't acceptable as I need an internet connection to the device.

With that said, there are ways to do it. Miraclecast (see https://github.com/albfan/miraclecast ) is the most well-known Miracast implementation, but I've never been able to get it working - I got it to work as a sink, i.e. I was able to cast to it, but only at about 0.5 fps, and as I said, I was never able to get it to work to cast to another device. It looks like you might need to use a special branch of Miraclecast to do it, and it's a work-in-progress - I'm not sure if it's possible to do at this stage.