dev-lang/python currently has no abi_x86_32 support, but packages depending on it do. C.f e.g. #578588 (net-fs/samba-4.4.2[abi_x86_32]), which cannot be easily fixed unless dev-lang/python also gains support for abi_x86_32.
This strikes my as something that would be very difficult to implement and just adds more complexity for 99% of use cases. Your time would be better spent figuring out a workaround for samba. -1 from me.
Adding another -1 as net-fs/samba-4*[abi_x86_32] also (for now) doesn't need python in order to provide the libs that other packages consume. This may change in the future but if or when it does occur the gentoo samba project will deal with it.
Closing this for now then.