Is there a glitch to walk through walls in Pokemon diamondwith out action replay or gameshark?

There are no glitches in Pokemon Diamond that allow you to walk through walls without using cheating devices like Action Replay or Gameshark.

These types of glitches are often associated with older Pokemon games, and they usually arise from bugs in the game's code. Pokemon Diamond is a much more polished game, and its code is less likely to contain such exploitable errors.

It's important to note that attempting to use glitches or hacks can potentially corrupt your game save data, so it's best to avoid them. Enjoy the game as intended!