Sublime audio:
https://sublimeacoustic.com/products/k231-stereo-3-way-active-crossover
you order the first set of crossovers installed and you can also order swappable crossover boards. Kind of like tube rolling? Find the crossover points that sound best, or just do the math/select by speaker capability.
Or just use fmod hi/low pass filters. Though, unless the amp has its own volume control, the fmods don’t give you the ability to “play with” relative power to each driver as the sublime does.
I bought my speakers wired for bi-amping though. I have no idea how you would go about “retrofitting” non-production bi-amp capable speakers to connect different amps to separate drivers.