In Minecraft Java Edition, it is possible to sneak between a 1.5 Block gap, but on Bedrock, that doesn't work. I don't know if it is a bug, but it's a very useful feature, that is just missing.

Steps to reproduce
1. Build a 1.5 block gap
2. Sneak
3. try to go through

On Java Edition you can just enter the gap, but on Bedrock, it doesnt Work (the Screenshots are from Java Edition)

Also Missing but useful and important features in Bedrock Edition
-the option to switch the main hand to left
-the feature, to stand in a trapdoor, close it, and crouch (see on the screenshot)
-the use of the new combat system:
    in Java Edition, if you press the hit button, you have to wait a bit, so you are making the          full damage again. This feature is also completely missing, you still can spam the hit-              Button on Mobs and other Players and will make full damage with each hit.
-The use of the second hand:
    the only things you can put in the second hand in Bedrock Edition, are Arrows, rockets            and a shield. In Java Edition you can put everything in the second hand, which makes it          extremely usefull for caving or exploring, because you can put things like torches and            food in the second hand.