In a small-sized bathroom, you don't really roam, and there are only two options for installing a washing machine - under the sink or opposite it, and even then, only if the door is located in the middle. For example, I didn't have to guess, since the entrance to my bathroom is planned from the narrow side. There will be more opportunities if you install a shower cabin instead of a bathroom - this way we free up another corner. A couple of new options will appear after combining the bathroom and toilet, but no matter how we put the washing machine, it will take up a significant area of free space, and nothing can be done about it.
To prevent a bathroom with a washing machine from feeling too small, try to leave the floor as open as possible - it is better to abandon the laundry basket and cabinet under the sink. Do not clutter up the room with unnecessary details: remove combs, cosmetic bags, washing and washing utensils out of sight - the bathroom will immediately seem much more spacious. 
White walls are preferred for small bathrooms, but not required. An interesting solution can be zoning with a contrasting color, as in the photo below. The massive washing machine in this bathroom with shower is specially positioned on the white side. Pay attention to the open floor. 
A narrow top-loading washing machine is a good idea for small bathrooms, it is a pity it is not as convenient to use as a machine with a front door. 
If the washing machine is built-in under a countertop with a sink, it can be hidden behind a door if desired. A similar idea is implemented in the photo below. Usually, washing machines installed in the kitchen are closed this way. 
In some cases, a niche for a washing machine is completely tiled, an idea that can be implemented in a combined bathroom. This option looks stylish and neat, but takes up a lot of space. 
And here is another example from two photos with a washing machine in a combined bathroom. In my opinion, the idea is not the best one, because the appliance door opens to the left, not to the wall. In addition, there is clearly not enough space in front of the car - you will have to load and take out the laundry through the toilet. 
This photo shows a more suitable option for installing a washing machine in a combined bathroom, the distance to the toilet is enough to load, and the door opens in the right direction. 
And finally, one more example of how to properly integrate a washing machine into a combined bathroom with a shower. Hope this topic was interesting and useful to you!
