It's pretty simple.
For the rocks;
You make a rock on layer 1.
Water on layer 2.
And then a "half rock", with water effect on top of the other rock, on layer 3.
For the shore;
You make a "hole" made of mountains on layer 1.
You then make water sprited like this:
The top 8/16 of the tile should be empty.
(Or the 8/16 on the right/left side for the sides)
on layer 2.
The water shouldn't have a built in shore.
And I only used one single color for the water, and I used RMXPs
built in "tileset-semi-transparent-maker".
I hope this helps
Also thanks for the great comments, I actually didn't thought I was this good