To be equivalent to the gravitational impact of Neptune the mass would have to be about 70,000 times the mass of Neptune. This is more equivalent to trying to f

To be equivalent to the gravitational impact of Neptune the mass would have to be about 70,000 times the mass of Neptune. This is more equivalent to trying to find Planet Nine [0], which, although was also “discovered” through gravitational effects, those effects are much subtler and the planet might not exist and if it does, hasn’t been found. [0] - https://en.m.wikipedia.org/wiki/Planet_Nine https://en.m.wikipedia.org/wiki/Planet_Nine