Am I still at risk of having a fat embolism if I get a fat transfer just to my hips?

Fat embolism is exceedingly uncommon following liposuction of thighs and flanks .  It is more common in fractures of long bones, but even then much less than the occurrence of pulmonary emboli.  Significant pulmonary emboli after liposuction occur at a rate of less than 1 in 1000.  Fat emboli occur at a rate less than that.  No type of liposuction is safer in this respect.  The treatment for FE is largely supportive.

You are less likely to get a fat embolism if fat is injected to just your hips. What is important in this scenerio is does your hip dip continue into the lateral buttocks. If so, you may not get that smooth look if all the "dip" is not corrected.