Not only does earth spin slower it's shape changes too

When glaciers melt from Greenland, North Pole and South Pole and off of Antarctica (which is a continent made of land under the ice), the ice turns to water and disperses all over the earth through the oceans which are mostly interconnected worldwide. This weight and mass causes the earth to rotate slower because of the water mass added to the equatorial regions and others from melting. But, in addition to this the poles become less heavy and the oceans become heavier in the center regions of earth (relatively speaking) which also changes the exact shape of the earth. So, this increases stress in new places in the earth crust and reduces stress other places.

For example, The Sierras and the Himalayas are both growing taller because the weight of the glaciers isn't there anymore so both mountain ranges are taller because of this. Likewise with more water pressure because the water is deeper there will be increasing stresses upon the ocean floor especially around the equatorial regions.

This in turn both in lower pressure places but also in higher pressure places likely will create earthquakes wherever stresses cause them on top of conditions already there.

So, global warming could theoretically create earthquakes that might not have arisen otherwise in addition to everything else it does. However, this would also be impossible for now to gauge I believe.