When I move with hwei, Brooding Painter that has Svellsongur, do I have 2 move triggers, and does each card discarded get its effect doubled?

Incorrect trigger joining, they are separate.

**Yes to two triggers — but the discard effect isn't doubled; it's duplicated as a whole separate ability.** Svellsongur copies Hwei's text while attached, so Hwei has the move trigger twice (its own plus the copy). Both trigger on the same move and go on the chain together — you choose their order (Rule 383.3.d). Each is a full, independent "draw 1, then discard 1, then [type bonus]" — so you draw 1, discard 1, then you finalize the reflexive trigger based on the discarded card and once it resolves, you do the same process on the resolution of the second trigger (chosen separately, and they can be different types). That means discarding one Unit doesn't give +6; you'd need to discard a Unit to each trigger to reach +6 Might total. Same for spells (draw 1 extra each) or gear (ready 2 runes each). This matches the established Svellsongur behaviour — copies create separate triggers, not multiplied effects.