Grim Hollow Trait Selection

-Grim Hollow Player's Guide.

"With the Heritage System, you can choose from a variety of heritage traits to build a character to your unique specifications. Are you a Dwarf who grew up in the cold Valikan tundra instead of under a mountain? You can reflect that in your heritage." 

"...a Grim Hollow campaign also allows players to build unique characters built on a diverse range of traits."

"But you can swap any of those suggested traditional heritage traits for any of the traits provided, building your character around any eight traits. This can include taking the traditional traits presented for any other heritage, taking one of your traditional traits again to gain its secondary effect, or taking any of the many traits that aren’t part of any heritage’s default presentation."

"You can reduce your Speed by 5 feet to gain an extra traditional trait."

I haven't found a way to do any of this in the D&D Beyond app.  Not implemented?  Or I dumb bunny no work picture box gud?

Any thoughts or suggestions?

The first post in this thread explains how this system has been (sort of half-bakedly) implemented in D&D Beyond. Support for it is fairly limited.