Thanks for sharing this, I love puzzles and that's a nice one.
Each combination of 4 pieces can fit in the frame. No need to flip them upside down.
It's not very challenging, but it's quite fun.
Green & blue
Printed at 100% scale. It's a bit big, it took me 5 hours to print the base and 5 hours to print the pieces, total of 10 hours.