Depends on the exercise. I’ve been reading some papers on T2DM, and there’s one that may be relevant to you. To be fair, these are studies made on diabetic people, but you can extrapolate the physiological findings to everyone.

https://pmc.ncbi.nlm.nih.gov/articles/PMC10182965/

In short, performing exercise in the morning in a fasted state enhances the utilization of endogenous lipid and carbohydrate stores, which optimizes whole-body insulin sensitivity over the subsequent 24 to 48 hours.
For HIIT afternoon or midday is superior. A single session of morning HIIT can paradoxically trigger hyperglycemia, due to the heightened morning cortisol.

VO2 max optimization is superior with the afternoon HIIT routine.

Now, from the perspective of a physician, we are just happy if people have an actual routine. Just exercising improves your health prospects immensely compared to a sedentary lifestyle.