xqemu is a low-level Xbox / Chihiro Emulator started in mid-late 2012 by espes.
The official homepage can be found at xqemu.com
There is a temporary compatibility list that was almost entirely created by pcmaker (also known as John Godgames) since 2015. The newest compatibility list from 2018 still has some problems though. You should not blindly trust these reports.
A major issue is that the version information for some reports is incorrect. This means that some games are reported as working, when they don't work in official versions (yet). They were tested with development versions build by developers, using incomplete features. Some of those features might also not be public anymore, so you can't even repeat those tests. XQEMU is also under development, new features in the official versions might have resolved some issues, or caused new ones.
You should only use these compatibility reports to get a rough idea about the state of XQEMU and where development is heading. You can also search for XQEMU videos on YouTube (like "XQEMU Halo") and you'll usually find something. Note that many of those videos are also made using development builds that aren't always public. Typically, the video descriptions contain more information about the used builds.
XQEMU-JFR is a now defunct fork of XQEMU by JayFoxRox. Most of the changes have since been integrated back into the official version of XQEMU. The archived version can be found at https://github.com/JayFoxRox/xqemu-jfr