What can help for general anedonia? including sexual
Too broad, it depends on the cause. There's no one fixed supplement or set of supplements that work for one particular symptom (e.g. the aforementioned supplements in the beginning of this thread do ZERO for my anxiety, but work great for the OP.)
So first I suggest you do everything you can to find out if your anhedonia is rooted psychologically/physiologically i.e. try to identify the route cause and then work back from there.
Having said that, for me personally, I have found N-Acetyl-L-Tyrosine to have intermittent benefit from me (I suffer from very persistent apathy/anhedonia and brain fog which I believe to be due to H2S Sibo.) Using N-Acetyl-L-Tyrosine will sometimes give me a sense of wellbeing/pleasure/motivation, but usually it only works when I've abstained from it for a reasonable period of time (the first time I ever used it the effects were super pronounced and I was able to create a good effect for a reasonable period of time.)
Your best bet may be to look at supplements that influence dopamine, that's generally consider to be the neurotransmitter that handles pleasure/motivation/reward and so anhedonia may suggest an issue with dopamine somewhere along the line (however that's a total over simplification of a completely complex system.)
Be sure to do plenty of research prior to messing with anything that field too. Amino acids tend to be harmless e.g. Tyrosine (because you've got rate limiting factors that prevent overproduction etc), but certain supplements e.g. Mucuna/Velvet Bean are regarded as being effective but potentially carrying much more risk with prolonged use.
Good luck!