G# min Maj7
"Hello, I would like an argument, please."
"Oh, okay, or would you like a lovely sounding guitar chord instead?"
This is a reverentially irreverent reference to an hilarious comedy sketch of the past, although timeless in quality.
Here we have a guitar chord that could be viewed a variety of ways. There is the tonic note on the low E string, fretting the note G#. Cool. Let's just take a moment to celebrate that integral fact.
And then after that momentary celebration, try playing this, and hear the cool vibe.
Unless we actually call that some other degree of the chord, but we won't.
Where the ambiguity here is the lack of a Third, neither Minor nor Major Third. It just isn't there.
So, how do we approach this? Context. Harmonic context. In real-world terms, that is best described as the chord played before it in a progression, and the chord played afterwards.
If the chord G# min9 is played before it, then it is highly likely this chord is naturally going to sound like it has a Minor 3rd note, even though that is not present in the structure of this particular chord.
There are two reasons for this ... the "ten-second audio memory collection of notes" that the ear-brain connection maintains. This is a difficult and nebulous topic to navigate, especially as there isn't much research done regarding this.
The second reason is simply musical logic, and compositional traditions. The key signature just doesn't often change tonality like that, from Minor to Major at the drop of a hat.
If it does, if the tonality does change, then there will be structures in place somehow to support the musical acceptability of this happening. And the chords afterwards are going to then usually, presumably, maintain that Major tonality for a good while, perhaps 16 or 32 bars at least, or in fact for the rest of the song.
To put this in a four bar chord progression, try playing G# min9 for 3 bars, then G# min Maj7 for 1 bar, and cycle like that.
This gives the option to improvise with G# Aeolian for three bars, and then adjust the sound subtly by playing G# Harmonic Minor Scale for one bar.
The only difference is that Aeolian has a lowered 7th note, and the Harmonic Minor has the natural 7th note - thereby capturing the sound of G# min Maj7 perfectly.
Now the only challenge is to make some cool melody vibes. And arpeggios are good for that.
Aeolian arpeggios for three bars, then Harmonic Minor arpeggios for one bar.
That's enough writing for now, although to find a cool G# min9 chord, try this page.