No, that interpretation is not correct. In the equation E = mc², the 'E' represents energy, 'm' represents the rest mass of an object, and 'c' represents the speed of light in a vacuum. It is important to note that this equation relates to the energy of an object, not its gravitational pull.
In the theory of general relativity, the gravitational force and the curvature of spacetime are determined by the distribution of mass and energy, not the energy alone. The mass of an object, as measured in its rest frame, is what contributes to the gravitational field it generates.
So, two planets with the same mass but different velocities would not have different gravitational pulls solely due to their velocities. Their gravitational pull would depend solely on their mass, assuming there are no other significant factors at play.
However, it is worth mentioning that the theory of general relativity does predict some additional gravitational effects related to the motion of massive objects. For example, a massive object in motion can generate gravitational waves, which are ripples in spacetime that propagate at the speed of light. These gravitational waves are predicted to carry energy away from the system and result in a gradual loss of energy and angular momentum. Nevertheless, these effects are generally small and not directly related to the object's velocity or relativistic mass.