If you are printing the dropouts, from a fabrication perspective it would be easier and stronger to print the stays' lug points directly on the dropout and then have a more traditional stay-to-dropout interface where the dropout has a round end that fits into the end of the stay tube.

After brazing it will look the same as what you have in the drawing, but you wouldn't have to cut that lug pattern in the interfacing parts, and the joint would be stronger because you would have more contact surface area at the braze joint. The round-end style I'm talking about looks like this, where those round ends fit into the seatstay and chainstay tube ends.




Let me know if that doesn't make sense. Fairly hard to put into words an idea about a complex 3D drawing