I'm not much on vegan or vegetarianism but I think they use liquid amino to fill in gaps. I did run into this guy on a podcast awhile back. He's doing keto in a veggie heavy way. But beware if your body isn't handling all of that vegetable matter well there maybe no way around it. Listen to your body. Your health is most important. Here is a link to his book.
Fat, Boost Your Energy, Crush Your Cravings, and Calm Inflammation: A Cookbook https://www.amazon.com/dp/0525537171/ref=cm_sw_r_other_apa_i_cgohFbWTM073W
If you're wanting to try more plant-based keto recipes, Ketotarian looks like it has some good ones. It includes 75+ vegetarian, vegan, and pescatarian recipes. I haven't tried the recipes myself due to the cookbook being expensive in the store I found it (Natural Grocers wanted about $30 for it!), but right now on Amazon it's only $11.