Requirements and technological advancements towards 6th generation (6G) wireless networks lead to enabling and development of massive low Earth orbit (LEO) satellite constellations to provide ubiquitous and high-capacity connectivity, particularly for maritime and airborne platforms. Consequently, new methodologies to study the performance of LEO networks are of great importance. In this paper, we derive both downlink and uplink analytical expressions for coverage probability and data rate of a massive inclined LEO constellation under general shadowing and fading. We model the LEO satellite network as a nonhomogeneous Poisson point process with general intensity in order to take into account uneven distribution of satellites along the latitudes. The results provided in this study facilitate the stochastic evaluation and design of the future massive LEO networks, regardless of satellites' exact trajectories in orbits.