What you want is an array of arrays, which Unreal doesn’t support very well (blueprint or native).
What you can do is create a new structure:
This you can configure very similar to Blueprint variables, so you’d set it up with an Array of bools. Then in your Blueprint you’d create an array of that structure that you created.
The only downside to this approach is that you can no longer easily do the same “Value equals 1100” sort of trick that you’re using to avoid the all the branching. But that’s the sort of trade-off you may just have to decide which is more important.
Alternatively you could give that structure 4 bools named Top/Bottom/Left/Right instead of the array. The equals check might work in this case, but you wouldn’t have the ability to hold an arbitrary number of values. From your description that might be okay since if you needed it you could edit the structure definition, something you wouldn’t be able to do with COLOR.
You could also try using an integer and doing manual bit manipulation, but that may be more advanced/complicated than you would like.