I created a mamba environment:
mamba create -n ijseg python=3.11 -y
mamba activate ijseg
pip install tensorflow==2.15 cellpose==4.0.6 stardist==0.9.0 csbdeep==0.8.0 pyimagej==1.7.0 numpy==1.26.4
After pointing Fiji to this environment and starting in python mode, I got the error:
bus error ./Fiji.app/Contents/MacOS/fiji-macos-arm64
I was able to start in python mode when using the "rebuild environment" button so it would seem there were simply things missing from my custom environment (at the least, appose-python it looks like).