Every fingering that fits a hand
ba98
hard
x668
moderate · barre · no 5
What is true of it
F♯maj7 is F♯, A♯, C♯ and E♯ — 1, 3, 5 and 7 counted from F♯.
On an instrument that cannot reach all 4, the 5 goes first, in that order.
The easiest of the 2 fingerings below is ba98: 4 fingers, held at the 8th fret.
None of them uses an open string, so this chord moves up the neck unchanged — the same shape 1 fret higher is the chord a semitone above.
1 of the 2 need a barre.
Where its notes are on the neck
The brass dots are F♯, the root. Everything else is a chord tone with its degree printed in it.
With a different note underneath
F♯maj7/A♯
3524
F♯maj7/C♯
6668
F♯maj7/E♯
aa99
An inversion is the same chord with a different note lowest. The name changes to a slash name because the bass is what a listener hears as the foundation.