Okay here’s a side-to-side that’s the same as my last one, but it goes across the other set of sides.

I cannot tell you how much time I have wasted on corner-to-corner. I really do think it’s impossible, although if you allow a connection to be like at a corner instead of at an edge it’s probably possible.

TBH most solves don’t have any path of 4 tiles from corner-to-corner. So requiring it be of one color seems…challenging.

I might try again with another colorway but, recently I’ve been doing jigsaw puzzles instead. This past week I spent 26 hours to do a 210-piece transparent, double-sided, solid-color puzzle. What fun!