Hey, Welcome to LD4all! If you haven’t already why don’t you introduce yourself in the BIG “Hi, I’m new here!” topic? 
You’re likely to run into some conflicting viewpoints here, but in theory what you’re asking is all possible.
For the rodent phobia, one option could be a sort of gradual exposure therapy. Conjuring up a rodent in an enclosed area nearby so that it can’t get to you, and then over time (Not just a few minutes, but days or weeks or even months depending on how you react to the therapy) you gradually make the rodent closer and expose it more until you’re more comfortable with it.
This is something that could be done in WL, but it would be easier to set up in LD for sure.
As for the second bit…well I’ve got no experience with self-hypnosis or subconscious…ah…what would you call it? Artificial subconscious self-manipulation…bah, whatever. 
I know other people here have tried that though, I’m sure one of them can give some info on their experience for you.