32-bit systems will be around a lot longer than HIP will be-- even longer so if HIP starts out of the gate with policies like unnecessarily shutting-out 32-bit users.
What build tools are you using?
You merely need to change the architecture target to x86/i686 in the Makefile / build tool options, compile a 32-bit EXE, and similarly rebuild or swap the bundled Python DLL for a 32-bit one. The compiled binaries identify themselves as 32-bit to the operating system when they're being loaded, and even your CPU won't care-- the instructions will be handled natively, since they're the same and just a subset of the 64-bit instruction set. Most of the programs you run daily on Windows are 32-bit, including CKII.
The ability to compile a 32-bit x86 program is independent of the architecture of the machine with which you're compiling it. Your build tool just needs to be told what to do. If it's what I'm thinking (a Turn-Your-Python-Program-Into-A-Binary tool, possibly even part of the official Python distribution), I can't advise too much, as I've not used it. Ultimately, any such tool needs a compiler, however, and there are only so many of those for Windows that are freely/easily available. Every single one of them supports compiling 32-bit programs out of the box. The compiler is what needs to be instructed to output 32-bit object code rather than its apparent default.
Did you download the tool / Python bundle from somewhere? If there doesn't appear to be an option for 32-bit in the tool and the documentation yields nothing, I'm sure that checking back at the source website would lead you to a 32-bit alternative download.
If the system uses a Makefile at all, then you're set. Within the Makefile, you will find the compiler clearly defined as CC = <compiler program name> near the top. You should also run into default Makefile options around there for ARCH (architecture) or TARGET or at least generic build options arguments that can be customized to use the correct command-line parameters for the indicated compiler to instruct it to build for i686. If the CC (C Compiler) is gcc or g++ or something with mingw in the name, then I am familiar with the build options for targeting specific architectures and can presumably help you out if you need it by then.
32-bit works for 100% of users and 64-bit for only 80% and lacks a single downside. Enabling HIP for the other 20% has, uh, a couple hundred upsides.