Engineering coupling between systems is essential for many phenomena of quantum physics and technology, especially in long distance without field overlap. We construct a long-distance cavity magnonic system to realize indirect coupling mediated by travelling photons. A high-quality dielectric resonator (cavity photon mode) and an Yttrium Iron Garnet sphere (YIG, magnon mode) are placed along the transmission line with a longitudinal distance of over 1 metre to avoid direct coupling. By tuning the longitudinal distance given by phase and the YIG sphere's transverse position, we realized indirect coupling in transmission: in the reciprocal case with the YIG sphere in the center of the transmission line, we have coherent and dissipative couplings at the longitudinal phase Φ=(2n+1)π and Φ=(2n+2)π; while in the nonreciprocal case with the YIG sphere on the side of the transmission line, we have coherent and dissipative couplings for the left- and right-going travelling photons at the longitudinal phase Φ=(2n+0.5)π and Φ=(2n+1.5)π. The coupled-mode theory modified by a higher-order coupling term is adopted to explain our results and enhances our understanding of long-distance coupling and nonreciprocity. Our illustration of switching long-distance coherent and dissipative couplings, gives access to designing nonreciprocal links and constructing advanced remote-control strategies among spatially separated systems to build networks.