The phrase "transports to fro" can be replaced with a number of synonyms, depending on the context of the sentence. Some potential alternatives include "shuttles back and forth," "ferries back and forth," "conveys to and fro," "moves to and fro," "carries to and fro," "brings back and forth," and "hauls to and fro." Other, related synonyms might include phrases like "transfers back and forth," "switches between," or "alternates between," depending on what specifically is being transported or moved. Overall, there are many ways to express the idea of something being regularly transported or moved between two points.