Okay, so any heterodyne receiver leaks a bit of the local oscillator (LO) signal back out the “wrong port” of the mixer, and out the receiving antenna. Sometimes more than a bit. That’s how the first-generation “radar detector detector” devices worked, and it’s how MobilTrak advertising works. It’s ostensibly how the TV-police in the UK would detect TVs and then compare them against the list of TVs they’d been paid for, and pursue the unlicensed ones.
The LO in any satellite LNB is probably detectable at some distance, but the strength off-axis would be determined by the radiation pattern of the antenna feed. Main boresight, sidelobes, all the usual. Outernet 3.0 is using a standard TV LNB, so assuming someone was looking for that signal, it would look like any other satellite-TV receiver. The LO frequency doesn’t vary depending on what signal you’re receiving, which is nice. If it’s legal in your location to have a satellite-TV receiver, simply get one that uses the same LNB type as Outernet, and set it up as a “decoy”.
It might be interesting to experiment with “choke rings” or shades/shields that would attenuate the off-axis signal, and if satellite TV is illegal in your country, surely there’s already an underground knowledge-base of how to do this.
On the wifi side, Outernet looks just like any other wifi AP. Nothin’ special. A little weak, even. Change the SSID and you should be good to go. If you’re concerned that someone may be looking for the specific brand (Ethernet MAC OID) of wifi dongles shipped with Dreamcatcher, just use ifconfig to change the interface MAC. Random values are likely to be invalid and stick out like a sore thumb, so copy the OID of another manufacturer and just randomize the last 3 bytes.