Are their names to types of desensitization and socialization methods for fear aggressive dogs?

For context my old lady is fear aggressive but after years of yelling at each other she's now made friends with my neighbor's tiny dog so now she seems to be less reactive if there's a small dog.

We've had interactions with two other small dogs that were roaming the streets (incidents were years apart) off leash and she did well but she also doesn't know how to interact and is very stiff and confused at what she's supposed to do next. Are their methods (with a trained professional) where there's kind of like a calm but indifferent dog as a mentor to kind of show the dog how to dog?

I know there's a dude on youtube with a doberman who does something similar but I don't trust him. It looks like he just brings the dogs together without any groundwork leading up the that point and just looks way too reckless.