Land reclamation by supporting slopes/hillside

Hello,

to secure the slope, protect the house from moisture (rainwater), and gain space, we want to support the slope with a wall. The wall should be made of solid stones. We want to embed the first stone about halfway into the foundation. The following stones will be laid offset (half stone offset) and filled on the inside with concrete/screed to ensure the wall truly holds. On the inner side of the wall (between the wall and the slope), we want to install a foil that should somewhat reduce soaking. Additionally, a drainage system will be laid there to allow rainwater to drain better.

My questions about the garden wall project:

- How should we construct the foundation for the stones?
- Is our solution/idea realistic, or will the wall collapse in a few years?
- How deep/wide should the foundation be? Does frost protection have to be considered for this wall?
- What else should we pay attention to so that this wall really holds?

Note:
The wall should be built with a "slope."
Dimensions:
- East side: 12.5 m / 3 m wide strip of soil between walkway and wall
- South side: 14.5 m / 90 cm wide strip of soil between neighbor (half carport, half walkway)
- Connection/slope: 4 m
Maximum height of the wall: 6 stones -> total height 120 cm, effective height about 105 cm - 110 cm

Stones:
Dimensions: 50 cm x 25 cm x 20 cm (hollow inside)

I would appreciate any advice on the execution.

Hello,

we have given some more thought to this project and have come to the decision to green the areas. ;-)