Steel beam visible in the corner

As far as I know, yes, but whether it can handle 2cm of steel?

I'm not sure if the multitool can cut through such a thick steel plate.

To use an angle grinder, you'd have to cut into the roller shutter box where the venetian blinds are. That is also not ideal.

Multitool alone won’t do it. And if you do, it takes forever and destroys dozens of expensive blades/discs.

I would rather leave it. Industrial look is in. Corten steel is in. :D Clean it and use it as a hanging plate ;)

If it has to go... maybe try with a metal drill bit to "perforate" the edge piece by piece as close to the wall as possible. Then try to remove the rest with a grinder and multitool, make it smooth. But you have to protect everything around well.

It would have been better to do that before the plaster. (The wall already looks plastered).

The ceiling is just resting on the plate? Is that okay for the structural engineer? I’m out of my depth technically, but the top plate does serve a purpose...

Is lowering the ceiling an option? It can also have additional advantages, such as easier installation for electricians, recessed lights. If not: who planned something like that? That person should take care of a solution.

Hello,

I worked on the corner over the weekend with various steel drills and a Bosch hammer :)

Congratulations, that looks much better right away.

Is this an architect-designed building in self-contracting? With a standard general contractor, I would have complained and had it corrected.