While all beanling and blightlings have base traits, and most have mutations, there are some visual differences that are not traits. This guide is to try and help you sort of the difference between style choices and traits!
Bean bodies
Beanlings and blightlings share the same basic body shape; A head followed by a vaguely tear shaped body with two arms and no legs. They way you choose to draw that body is widely up to you! you can choose to make them very pointy, very round, have a differentiated torso, or not! As long as the body does not become long and snake-like, or add aditional segments, which are both traits, you can draw it as you please. The image below shows three examples of slightly different bean body shapes that are not traits. The last body shape is elongated with a trait for comparison, which you can of course have if you have the proper items.
Bean Arms
Much like bean body shapes, bean's arms can vary quite a bit visually as well. You can make them as defined as you would like. As long as they don't have more than 2, it's not a trait!
Similarly, bean 'hands' are not standardized. They can be paws, humanesque, bug, insect -like, etc. The only thing to keep in mind when drawing your bean hands is that claws are a trait! So you can add claws, but you must have the proper items to do so.
Wishes, Curses, and Wings
Beanling's wishes and Blightling's curses naturally stem from a beanling's back. If they come from anywhere else on the beanling, it is a trait. Some beans have wishes or curses and wings that come from very high up on their back, while others are lower. The green area on the back of the bean below shows the area in which the wings, wishes, and curses can stem.
Wish and curse tags are generally a fairly thin, white ribbon-like material. They are printed with the wish or curse that brough thte bean or blight to life. The end of the tag can be shaped without it being a mutation. However, tearing, piercing, or other decorative elements attached to the wish are a trait. The 'writing' on Wishes and curses can be almost anything, as long as it is not offensive.
Bean Heads
In general, beans tend to have a sort of squashed chibi-proportion head and face with a rabbit-like nose. This is not required, and you can essentially give your bean any basic head shape you would like. Beans can have more and less defined faces, longer muzzles, noses like other animals, and a lack of cheek floof.
Eyes are also widely unrestricted by traits. If you want to give your bean multi-coloured, multi-pupil eyeballs, you certainly can. The only thing to keep in mind is that having more or less than two eyes is a trait. 
Lastly, Beanling and Blightlings have hair that cannot extend beyond their shoulders. When they grown into Flowerlings or Witherlings, they can have hair of any length!
