Here's my article on dulcimer Modes and Modal tunings. It has all the Modes, their traditional tuning, and the key of D equivalents.
I think your inquiry about Phrygian Mode is only the second or third I've seen in 40 years. It's just not a Mode that anyone wrote or writes music in, in the last 200 years or more. In that same 40 years of playing, I think I've tuned to Phrygian Mode perhaps twice; for the same reason -- No one has written any music in Phrygian that I have any interest in playing.
Open Aminor tuning -- No matter which way you go -- high or low Am -- you're going to have to change strings to tune to mthe key of A (Bass string is A or a). AEE is the baritone Ionian tuning which could also be AmEmEm of course. AEA is Mixolydian, so AmEmAm. Same thing going to the high a.