How will plate tectonics change hawaii in the future?
By changing subduction directions.
So firstly, Hawaii is the result of hot-spot volcanism this is a type of volcanism that arises from mantle plumes. These plumes are believed to originate from the core-mantle boundary (still debate) and migrate up until they pierce the crust.
The cool thing is that plumes are believed to remain stationary whilst the tectonic plates move over the top of them. Think of holding a pin under a piece of paper and then piercing the paper repeatedly. Try doing this whilst you move the paper from left to right, what do you see? A line of holes in the paper.
Now lets imagine the mantle plume is the pin piercing the oceanic crust whilst the crust moves over the top of it (due to plate tectonics). We will see a string of volcanoes as a result. This is exactly what we do see when looking at Hawaii from above:
You can see the line of volcanoes stretching from the present Hawaiian Islands (on the right) all the way back to Pacific ring of fire boundary. This is know as the Emperor Seamount Chain and is just like the pin and the paper. The hotspot that created Hawaii has been piercing the oceanic crust as the plate keeps moving over the top. It has been going on so long that some of the older islands are now being subducted (at the top of the picture)!
So back to your question, plate tectonics will determine where the Emperor seamount chain goes next. A change in subduction direction could cause the seamount chain to gain another bend as you see in the picture. The bend in the picture is the result of changing the direction of plate movements.
Try the pin and the paper example, pierce the paper (from below) at a constant rate and slowly move the paper in different directions, see how the pattern changes!