Hotprop is correct in saying that you need a ME-IR to fly a ME aircraft in IMC, and also correct in saying that a ME-IR also allows you to fly a SE aircraft in IMC (as long as you have a valid SE class rating, of course!)
However, don't confuse this with a multi-pilot IR. A multi-pilot IR does not give you any privileges on any single-pilot aircraft. Although this is a very different thing to a ME-IR, I think it causes a bit of confusion simply because they sound similar!
FFF
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