Right.
Choline helps me with anxiety, too.
I don't tolerate most supplements well, so I can only recommend few that I tolerate.
Vitamin B3/ Niacin needs tryptophan for synthesis and B3 tends to help me eat less carbohydrates. It's always said that carbohydrates are good for raising tryptophan, so maybe B3 helps by lowering tryptophan requirement?
I had gut problems with histamine intolerance for a long time and had to eat a lot, too. Vitamin B2/ riboflavin helped with that. It sometimes induced anxiety and worsens my mood though.
I also take hydroxocobalamin/B12, but I am testing dosage and best way to take it at the moment... a bit unsure there.
In general, I think supplements that effectively strengthen fatty acid oxidation and energy metabolism could help, so that you have more energy to produce glucose for the blood sugar.