Window reveal before window installation... smooth coat?

Currently, it looks like this.

That could have been done more neatly with filler putty instead of mortar (and/or with more care), but it will probably "affect" the subsequent plasterer the most. The window installer will probably work with brackets and set the window frames to the outer edge of the wall. If he adds his two cents, we'll know more - currently, I can only speculate about the installation level based on the specified wall structure.

This could have been done more neatly with filler putty instead of mortar (and/or with more care), but it probably "hits" the following plasterer the most afterwards. The window installer will probably work with angles and set the window frames to the outer edge of the wall. When he chimes in, we'll know more – currently I can only speculate about the installation level from the specified wall structure.

In your opinion, should I have this done or take it into my own hands, or would the windows still be airtight and pass a blower door test..?

Without knowing the installation level, one wouldn't even know which area should be improved before someone continues working on it. The window installer has his own mouth and an opinion on what conditions he needs for proper work. I don't see any cause for concern there, purely abstractly at first.

I would first ask the shell construction company if this is the final state and then ask the window installation company about the preparatory work required on the construction side and proceed accordingly. After all, they have to provide a warranty for their installation later. But at the latest during the measurement appointment, you will get feedback on this anyway.

is of course right that it ultimately depends on the quality of the installation surface. In general, it would have only cost the shell construction company slightly more time and material to apply a continuous smooth coat instead of the patchwork. Unless they are planning to do this anyway.

@11ant is of course right that it ultimately depends on the quality of the installation surface.

First, one has to decide where it should go.

In general, it would have cost the shell builder only slightly more time and material to apply a continuous smooth coat instead of the patchwork. Unless they still plan to do so anyway.

Probably not, that already costs considerable time, and the plasterer inserts a mesh there. So the "condition before plastering" is probably considered "finished."