A while ago I remember reading a blog post about the (in)famous dw > (e)rk sound change in Armenian. This post discussed it in terms of feature metathesis, i.e. the stop feature and the continuant feature swapping places. It drew comparisons to examples in many Iranian languages (which have been in close contact with Armenian since before its earliest attestation).
Unfortunately, since then I have forgotten what these examples were, and unable to locate this blog post.
The closest I've been able to find is Jessica DeLisi's 2013 paper *Feature metathesis and the change of PIE dw- to Classical Armenian -rk, which discusses Iranian parallels, but ultimately settles on a phonotactic requirement that in CC clusters the first element must be more sonorous, rather than (unmotivated) feature metathesis.
Does anyone know of any examples of fairly uncontroversial feature metathesis in consonant clusters (especially in the Iranian languages), especially those that leave place unchanged?