I have never heard of favism. Can you have peas, nuts, seeds, soy and/or gluten? If so, then you should have no problem. I love beans and ate it every day pre-vegan and I think that on a mostly whole food vegan diet, I have actually eaten it less than i used to
One method you may want to try out is supplementing with amino acid powders, especially lysine and maybe taurine and others. Some websites like myfooddata dot com can tell you the amino acid balance of common foods like oatmeal. Then you can plan to supplement with the amino acids your foods are low in. Lysine, taurine, and some other bulk amino acid powders are manufactured by fermenting grains with specific bacteria, and so are vegan. If you try a vegan diet you must make sure you supplement with docosahexaenoic acid (DHA),available from algal oil. Also b12 and probably b6 and minerals like zinc and iron. There are vegan multivitamins available if you want a specifically vegan supplement.