Probably not. Because, zukes have much more water contents.
Also, anything that has too much water content is not quite suitable for pickling. For example, not every cucumber is fit to be pickled. That is why there is a variety called PICKLING.

But, on the other hand, you can pickle zukes too but need to use more vinegar. How much more? I don't know.

1. No. More free water and more alkaline pH.

You can sub zucchini for cucumbers in most of the NCHFP/Ball tested and approved cucumber pickling recipes for canning as long as the amounts are not changed because they all contain sufficient acids and safe processing and storage instructions. But other recipes and other methods of food preservation may not be safe for substitution and have to be evaluated individually.

2. No. "Everything" is way too broad and slices when another form is called for can end up as mush. The best use for overly mature cukes and zukes is grind/shred for relishes or chutneys.

Dave

Thanks, folks!