To my knowledge, any downsampling done through GeDoSaTo kills the depth buffer in the game. I've never seen a game (which exposed a proper depth buffer normally) that still had depth buffer access after downsampling in GeDoSaTo.
This is incorrect regarding Mass Effect 2 and 3. Depth buffer access in reshade is only (to my knowledge) possible when downsampling one step in gedosato. I can't speak for other titles though.
I'm not sure about downsampling one step as every time I have used GeDoSaTo downsample resolutions to render down to my native resolution (1920x1080) the depth buffer is not present. The only way I've been able to access the depth buffer when using GeDoSaTo was to render down to the same resolution that is also available as an NVidia custom resolution or in this case a DSR resolution. The main reason for this in my case was to use the GeDoSaTo HUD removal as well as ReShade depth shaders at the same time.
This was done by forcing the presentWidth and presentHeight values in GeDo as below.
Code:
#forcing downsample resolution to actual NVidia custom resolution for ReShade effects to be applied to full image and not downsampled image. Running game at same resolution.
clearRenderResolutions
presentWidth 5120
presentHeight 2880
presentHz 60
Using the above method I was able to used depth based shaders DOF, outline, emphasize, and ambient occlusion along with GeDoSaTo's HUD toggle in the below image.