Mercenaries: chance for 'special' portrait from packs?

Hi there,

So, I’ve been wondering for some time: currently, we’ve got two mercenary portraits (for Tyrael and Elise) that can be claimed by completing their respective achievements. Are they ‘reserved’ for that particular way of obtaining them only, like some portraits one could get from events or reward tracks, or could they be received from packs or other means (bundles, for instance), thus making also the achievements essentially meaningless?

[Updated]

Alright, turns out a portrait for Tess can be earned via an achievement (and if it’s supposed to be a reference to something, I don’t get it), however, I’ve already obtained it from packs. Thus one may want to prioritise achievements for Elise and Tyrael in order to maximise their possible gains and avoid potential frustration.

[Update 2]

So, I’ve done the achievement for Tess, and the reward was 50 coins, as if the portrait from it was converted, according to the support article. However, it should be noted that I’d had all Tess’s portraits already; some Reddit post stated that otherwise one could get another unowned portrait instead.