But really I'd say middle and neoplatonic mystery religions.
How so?
Because they deemphasize/denigrate matter in favor of pure spirit?
I don't think it's any one thing. It seems like every time I hear about one of these "anti-sacramental" positions pre-1200 AD, it's attributed to a group or figure affiliated with (rightly or wrongly) the mystics, sages, gnostics, etc. of middle/neoplatonic religion--that strange, vague milieu ranging across a vast spectrum from middle/neo-platonized Abrahamic religious (The Fathers, Avicenna, Maimonides) on the one hand, all the way down to distinct religions (manicheanism, pre-Christian hellenistic mysticism) on the other.
I'm becoming more familiar with the accounts of such groups in the West, but I'm just starting. What I can say by way of initial observations is that the western sources can be divided into two rough groups:
First, the outsiders, like Catholcis, who focus on how the groups' actions appear to them and the scandalous implications of their supposed practices (they "abhor" liturgy, have women "lead" things as prophets, share things in common). It may be that these commenters don't have the philosophical/theological/historical context to understand these movements the same way that, say, Alexius's Constantinople did, so for all we know they are radically misunderstanding them. It could be that these groups like the cathars are just classic bogomils with a few quirks. It could be that the western commentators (to be very speculative) couldn't recognize, say, archontic cosmology because the Waldensians kept it relatively quiet and it would've seemed rather odd and confusing and nonsensical to the uninitiated.
The second group is the "victors" who wrote history--the zwinglians, anabaptists, baptists, etc. They tell the story as it suits them: Groups like the anabaptists and their supposed spiritual predecessors rejected authority in favor of a return to the perspicuous early church, had biblical doctrines, the authorities came and martyred astronomical numbers of them for it while they were minding their own business (the anabaptists seem to believe that 4 out of every 2 anabaptists were killed--can't pick them out for it, the Russians do the same about the Soviet persecutions). Maybe these accounts fail to convey the "secret" doctrines of their groups because they're scandalous, were lost, were superceded, or they never existed in the first place. Once again, highly speculative.
Will say, though that the bogomils were in Strasbourg, IIRC.