Freezing the trim while wet will add water into your extraction process. If you are making budder, most water will simply boil off. If you are making ice water hash, it will simply melt off into the ice water. No biggie.
now if you are making quick wash ethanol extractions.... you will be adding water into your process which will lead to more undesirable elements in the final product.
So it really depends on what you are planning on doing with that trim.