Where to get expert advice for each camera make

Dear all, I’d like to start a small macro-photo project with a program I’d code myself. I will need focus stacking integrated into the camera (assembly of focus bracketed pics) to compensate for the very small depth of field of macro pictures, but also a good sdk to send commands to the camera and receive the pictures - and of course a good macro lens must be available for the mount (with converters if needed) and the camera should have a decent resolution if I want to see some details on my photos.
I have tried going to photo shows and asking the reps from the different manufacturers. Half of them, if not more, do not even know what their cameras can do (« it’s too specific for me » is the typical answer, the other answer being « we don’t have that functionality » then another customer nearby tells you that they do have it on some models), mix up focus bracketing (just taking pictures at different focus lengths) and stacking (doing the assembly of these bracketed pictures), have no idea if an SDK is offered by the brand.

Sending help request using the forms on the manufacturer’s local webpage is useless, it is often the same people who answer and have no better idea.
These two properties I am looking for are not often detailed in online reviews, which makes the search even more difficult.
Would someone here have good contacts (i.e., competent people) at various manufacturers that they could share in mp ?
If you know about cameras that can fit the requirements, I’d appreciate that too, it’s even easier than asking the manufacturers..

For what it's worth:

Olympus / OM System TG-3 (and later models?) I recall there being some sort of super-macro mode which stacked images in-camera. But stacked images were available in JPEG format only. I don't recall the feature being available at all focus ranges, or offering much user configuration options.

Nikon Z, including Zfc Focus-bracket only, size of available focus steps is relative and simply indicated as 1-10.

Certain Sony models including A6700, A7R5, but not A7R4 Focus-bracket only, relative focus step sizes similar to above.

Adding to 4season's reply...

• Olympus/OM System OM-1 or OM-5: Natively supports both automated focus bracketing and in-camera stacking, avoids PC-side batch post-processing. Their SDK (OM Workspace and developer support) is well-documented for image retrieval and automation. Several sharp, dedicated macro lenses exist for Micro Four Thirds.
• Panasonic Lumix G9 II and S5II: In-camera stacking is built-in, and their LUMIX Tether SDK gives remote access and image download for committed workflows.
• Nikon, Canon, and Sony: All three offer focus bracketing (not real-time stacking), meaning you must use third-party stacking software (like Helicon Focus or Zerene Stacker) post-capture. SDKs for automation, remote capture, and image download exist, but stacking needs to be coded externally.