Unweighted muddlers with a long thin leader fished using a sinking line is the closest thing I can get to an eratic side to side motion of a baitfish. Hard three to four inch strip followed by a pause. It cause the fly to have a fairly side to side motion where the fly usually ends up.

Start by fishing it on the top waiting for your line to sink then use the hard short strips and pauses will get the fly down and cause it to somewhat suspend.

Adding weight to a fly in my mind kind of limits any other action other than the rise and fall.

Probably my go to setup for any species of fish.