Running applications on a different architecture than the one for which they were compiled is a common occurrence, not in the least with Apple’s architectural migration every decade or so. It’s also commonly used with for example ARM, OpenRISC, and RISC-V systems to run applications that are only available for x86 or x86_64. While QEMU and kin are often used here, they’re pretty resource heavy, which is where an option like Box86 and its 64-bit sibling Box64 are attractive options. Unlike QEMU, both offer dynamic recompilation and redirection of dynamic library calls to native libraries, including those for SDL and OpenGL.
Both are available on GitHub under an MIT license, with Box64 probably the most interesting these days as applications and games have moved on to a 64-bit only world. The only hard requirement that Box64 has for a host system is that it is little-endian, which is a pretty easy requirement to meet. The most recent release was on March 10th, with Box86 0.3 and Box64 0.2.2. As essentially a translation layer, it does not offer full compatibility with every bit of software out there, but it’s already good enough to run Steam, GoG, and Epic Game Store clients and install and run Windows games via Wine for x86.
A simple set of benchmarks comparing it with QEMU and FEX (another emulator) shows it to run both more applications, and with significantly better performance.