The hearing and seeing issues might be part of why she is reacting to other dogs.
She probably smells them, or sees that something is moving, but has trouble figuring out what it is or how close it is. Not knowing would make it scary, so she barks and growls in hopes it will stay away.
Has she always had issues with other dogs? Or did it only start as she got older?
If her reactions are really because of her own physical problems, and those problems keep getting worse, then training might not work very well. You might think about how to keep her far enough away that other dogs don't upset her, rather than trying very hard to train her to tolerate them.
I lose track of whose dog is how old, so I hadn't realized she had these other issues going on. Now I wonder: maybe she's having trouble with her sense of taste, too. That would explain her reduced interest in the treats.