Edit Bed_Mesh values or adding multiple probe z-offsets

Basic Information:

Current Klipper Version | Mainsail

Hi everyone,
I have a question regarding the bed_mesh.
I want to edit some of the created mesh-point-values after the probing is done, maybe via an extra macro.
It are always the same, “correction values”, but different ones for the specific probe-points and all of them are relative to the measured values.
As comparision:
In Marlin I created and used an extra gcode-file with several commands like “M421 I3 J2 Q-0.123” to edit some of the Mesh-points afterwards, so i could use it if I wanted.

Is there a way to do this in Klipper / Mainsail?
I thought about an extra macro i could execute, if needed.

The measured values are stored in the printer.cfg, maybe there is a way to edit some of them relative to their “current values”?
I also only use one mesh (default).

If that is not possible
Another solution would be - is there a way to add one specific Z_OFFSET for each leveling point?

Want to compensate the X-gantry - misalignment of my printer (Anycubic i3M).
Found a lot of “topics” but none of them helped me so far.
For example:

Thank you all in advance!