Is brain swelling inevitable after right-side ischemic stroke?

No it isn't : Brain swelling depends upon the size of injury and whether there has been a hemorrhage . Larger strokes more likely.

Size of stroke: The amount of swelling, or edema, around a stroke is related to the volume of tissue infarcted. For a small stroke, swelling shouldn't be a problem. For a major hemispheric stroke, swelling can be life threatening and even sometimes require brain surgery to relieve pressure caused by the swelling.