Procedural Creation of Edges for Platforms

So, i’m building a game where everything is pretty much going to be on floating platforms, and how I want to build those platforms are with sort of a library of puzzle pieces that I can arrange to my heart’s content in as many different combinations as I want. However, I also want all of those pieces to have nice border/edges that match the design/style of the pieces, and I want to be able to, hopefully, have it all look seamless. Now, for certain styles, like metal or industrial, those I feel can be modeled separately if need be because they aren’t going to look like one long, flowing piece. For nature themes, however, I think this presents a problem as I don’t want there to be a bunch of noticeable seams everywhere. So, I was wondering if there was a way to build a few standard pieces that fit well together and use blueprint to edge all of my floor pieces in said themes. An example of this would be the edges on the left side of this picture, how the rock doesn’t seem to have seams as well as the slight bump on top of the siding rocks. Just any way to procedurally add things to the edges things would be nice.

With stuff like that you create several different assets that would fit together but have enough things different to break things up so they don’t look tiled. So you would start with figuring out each possible type of piece needed for any edges, and then to add some variation you would build a few different versions that could be randomly mixed together.