Recently, I discovered a bug that is a visual glitch, that the end realm sky can appear in the overworld. It is the end skybox appearing in the overworld. Until it is fixed, here's how to do it:

1.  Perform the overworld sky in the end glitch. (MCPE-46865)
2.  Make sure you're in creative mode.
3. Turn off the command blocks enabled gamerule. (optional)
4.  Only do #3 if you have any /tp command blocks. (the actual command)
5.  Turn back on the command blocks enabled gamerule.
6. Enter the end portal until you see the end realm sky in the overworld.
7. Bam! That's how to do it.

This is a visual-only glitch, as with MCPE-46865, the overworld sky isn't supposed to be in the end, but with this the end sky isn't supposed to be in the overworld. Mojang should fix this, so that the end and the overworld can each have their own skybox. Thank you.