Scales to Play Over A#7sus4
Every chord is a subset of several scales: any scale that contains all of a chord's tones fits over it. Pick a chord to see the matching scales from its own root, the major keys the chord belongs to, and full fretboard diagrams for every scale on guitar.
A A#7sus4 chord contains the notes A# – D# – F – G#. Any scale that includes every one of those 4 tones fits over it — from the root A#, that means A# Natural Minor, A# Minor Pentatonic, A# Blues, A# Dorian, A# Phrygian, A# Mixolydian, A# Dorian Bebop, A# Mixolydian Bebop and A# Spanish. Start with the first scale listed: it is the most common choice, and the others color the same chord tones differently.
A#7sus4 is also diatonic to 4 major keys: C# major (relative minor A#m), D# major (relative minor Cm), F# major (relative minor D#m), G# major (relative minor Fm). In a song from one of those keys you can also solo with the key's own major scale or its relative minor pentatonic across the whole progression, not just this chord.