Using /setblock to place a "the_aether:blue_portal" block creates the aether portal, but you can't travel through it.
Using /setblock to place a "customportals:customportalblock" creates a black nether portal that also doesn't work.

Update: The portal works when setblocked on top of glowstone. This suggests that there is some unnecessary check for glowstone, either by this mod or by the custom portal API you're using.