If its a true anchor, like POSes or GSCs have, then it would work the same way. You would activate it, and after a delay your ship would be fixed at one spot. There would have to be distance limits like there are for GSCs: A ship cannot anchor within some distance of another object. (This prevents people from blocking a station undock with anchored ships). Maybe 5 km?

In addition, an anchored ship should remain anchored even if you eject from it. This would stop issues with ships getting bumped out of POS fields and all the petitions that result. It would also give supercap pilots confidence that if they left their ship in their POS, it will still be there when they return. (And now Im nerfing myself. I once stole a Proteus that got accidentally bumped out of a POS field by the enemy when they warped in a Nyx.)

A bump reduction module would be sort of like a personal web. It just greatly slows you down, and increases the "drag" factor of your ship. The issue here is not to make it an insta-warp module. Maybe it not only slows you, but prevents you from warping.