Since meat and veggies often cook at different temperatures, you can technically place both in the same water bath, but we can’t vouch for the results.
We do have plans to add meat/veggie combo cooking options in Smart Mode in the future.
In the meantime, if you are feeling adventurous, feel free to experiment using Manual Mode! Another option is using Mellow for your meats and before serving, you can sauté, roast or steam some veggies to add to the dish.