Facing simlar issue I managed to build the wxPython 4.2.3-r1 after downgrading sip from 6.11.0 to 6.10.0. I am using Python 3.13.
Sip 6.10.0 seems to be required: https://github.com/wxWidgets/Phoenix/blob/wxPython-4.2.3/requirements/devel.txt