Are yarrow and meadowsweet interchangeable?

[piojo]

A batch of mead was too sour, so my friend and I backsweetened it. When the sourness was reduced, it was too sweet. We added a tea made from meadowsweet (7 g boiled in 200 mL of water) and it nicely reduced the impact of the extra honey.

We also made a similar tea from yarrow, but didn't end up using it. The yarrow and meadowsweet didn't taste that different (mild herbal tea taste), and my perception was that either would serve to blunt the honey's sweetness but would not really add its own scent/flavor. Are these herbs essentially the same, and if not, what would make a recipe use one over the other?

 

[Miraculix]

They both taste completely different to me. Yarrow can get into urin-ish territory taste wise if overdone, never experienced this with meadosweet.

 

[piojo]

They both taste completely different to me.

Do they have a strong taste to you, and something that will come through in the end product? Can you tell me how you use them in addition to balancing sweetness?