Just about all the cross-steer axle setups I've seen have a panhard bar.

Never seen a panhard on a side-steer (fore & aft draglink) setup.

A panhard on a cross-steer setup makes for a solid steering car since it doesn't allow the drag link to push the chassis sideways on the shackles.
All steering inputs go toward moving the steering arm.

More consistent steering on corners as well since centrifugal force on the chassis doesn't create steering inputs.
The panhard resists the chassis centrifugal forces.