The SCAD for this is original but is based on the image of the downspout I say I am remixing. I wanted to do my own and this one has different dimensions for the downspout tubing.

This is made such that the top accepts a crimped pipe and the bottom mimics a crimped pipe.

SCAD source is provided.

I printed this in PETG for use outside and used no support. Printed standing as STL shows.