Ive never heard of anyone substituting love for rats but if it works
As for switching to live, why do you want to? Its easier to feed f/t because you can have weeks worth of food and simply have to thaw it instead of sourcing live rats every week or taking care of rats to be fed off. Also there is no risk of injury from a dead rat, to feed you thaw and then use warm water or a hair dryer to heat up before presenting on tongs.
If you want to switch to live you can place the prey in with your snake and they will know what to do. But make sure you are there with a pair of tongs or something to intervene with if needed.