Draw out a 2D floor plan with ALL measurements. It doesn't look like you have enough room as you want it because you wouldn't want a shower smaller than 36" wide.

I hate pocket doors on a bathroom. They never feel private enough and have less sound proofing. Could you have the door swing out into the hallway instead of in to the room? That is what we have recently done with a tiny bathroom we are remodeling.

I don't love your layout, but think there are other options for more optimal layout in this space. Best if you can upload a drawing of your space with measurements. Even a basic pencil drawing is fine. Also, have you looked at what is involved in changing the location of your plumbing fixtures?

This is the layout we were thinking, we can fit a 36 in shower in the corner

Other barrier is this: bedroom door opens into the bathroom door, so we were going to ask the contractor about moving down the opening, but then having a smaller corner shower

If the contractor says you can move the door then move it all the way to the left corner, build the shower in the corner where the door is now and put the vanity in front of the toilet

@J Steel's idea is good because you don't want to have to move the toilet. It's the most difficult fixture to move, and you don't want a direct view of the toilet when the door to the bathroom is open.

Could this work? You wouldn't have to move or change the door. There is an easier walking path than with the green tape lines you have proposed. You would not have to do a diagonal shower entry. Not sure how the ceiling slope would impact my suggested shower placement.

Look at pics of NYC bathrooms and you will open a world of possibilities for small spaces with good layouts.

I wish, we have a sloped roof/ wall in that corner

would need to change the existing door to a pocket door, which we arent thrilled with.

You're right to be wary of a pocket door on a bathroom -- oh, they're great in the right places: a laundry room or pantry that's usually left open -- but they're all wrong for a door that's opened /closed multiple times a day. They're harder to use (especially for children or elderly people), and they will break, which may necessitate a professional's efforts to fix.

Have you considered changing the swing so that the door opens outward? I have that in my bedroom /bathroom, and I never think about it.

you wouldn't want a shower smaller than 36" wide.

Well, my hall bath replaced an old tub, and it's 60x30" ... but that's only okay because of the 60".

you don't want to have to move the toilet.

Moving a toilet is also expensive.

My own thoughts:

- In general, bathrooms work best when the shower (the largest item) is placed at the back of the room. Could you do an across-the-back wall shower & replace the current window with glass blocks (to avoid water problems)? Glass blocks are now available in colors and patterns and can look really nice. This would mean moving the toilet, which isn't ideal. The slant inside the shower would be okay.

- This would then allow you to place the toilet and a small sink on the left-side wall.

Moving a toilet is expensive because of the pipes that need to be moved. What is below the floor? Basement? On a slab?

Measure out the shower size you're hoping for. How long the toilet is. The vanity size you want.

I agree about pocket doors not feeling secure enough for a 'public' bathroom. But pocket doors to your own en suite aren't so bad. Presumably it's only used by you/your significant other.

I would try a sink where the hamper is, move the door to the other corner where you are showing the shower, and put the shower where the door currently is. A sink can be put on a wall that drops to 60" at the back according to IRC.