Omni-manipulation is the same as Omnipotence. Omni-Manipulation is a form/expression of Omnipotence, so they essentially have the same capabilities but through different methods.

Omnipotence is being capable of doing everything while Omni manipulation is the power to manipulate everything

Their difference is that omnipotence can do anything because they can and Omni manipulation can manipulate everything to allow them do to anything for example an omnipotent can just fly because they want to with no reason whatsoever while Omni manipulation can control gravity to achieve fly