Ellacor Micro-coring or Morpheus8 - which of the two deliver better results when tightening the lower face?

That still remains a tough question because Ellacor is so new and Morpheus (in my experience) is very dependent on who is doing the treatment. I've seen great results with aggressive Morpheus and for those who didn't get the amount of tightening they had hoped for I've started to offer Ellacor.
Between those two treatment modalities, I think the majority of loose skin can be managed without a knife. Best Wishes!!

While looking at the design of these two devices they look as though they are similar procedures, however it is the intention of them that is different. Ellacor is intended to be a bob-surgical skin removal device, while also working to tighten the skin. Microneedling procedures such as Fractora and Morpheus are intended to be skin tightening and resurfacing devices that both use radio frequency or heat as a major component.

Without photos, it is difficult to comment in any but the most general way. What can be said is that If there is sagging and jowl formation of the lower face and jawline, robust HA fillers have a proven track record (when injected by experienced physician injectors) for achieving nonsurgically and noninvasively immediate results for straightening and defining the jawline and treating jowls along the jawline. And if the problem is accordion lines and parallel laugh lines of the lower cheeks around the mouth, this, too, can be improved by injection of an appropriate cohesive, low viscosity HA filler properly injected in the region. By contrast, you would be wise to exercise a great deal of "buyer beware" when evaluating so many of the here-today-gone-tomorrow, relatively expensive "bells and whistles" light and energy-based treatments, etc. that are backed far more by heavy marketing hype than hard science. To lessen the chance for "buyer's remorse," you would be wise to consult with a board certified cosmetic dermatologist. Hope this helps. Best of luck.