Not an easy task
Keto simply means no carbs diet.
It means no grains diet, no sweet vegetable, no carrots, no beats, no onions, no sweet fruits, no potatoes, .... and those vegan foods are often 50% - 90% of common vegan diets!
It means, diet is based on vegan fats and vegan proteins like tofu.
The questions is, can you live long time on a diet based on beans and nuts?
Can your intestines tolerate a lot of beans ? Is your blood type A ?
Fats and proteins in vegetarian diet come mostly from beans and nuts.
Avocado has some fats.
Eggs and milk have fats and proteins, if you can tolerate it ?
The rest of the diet are green salads made from low Sugar
vegetable and no grains seeds.
You can live on this diet for a limited amount of time, but it may make your condition worse on the long run.
Most people on keto diet eat eggs, meat, fish and seafood.
Once you remove eggs, meat, fish and seafood, not much is left.