To begin with I will try to explain the concept of soloing over an A minor blues. Since in a minor blues every chord tends to be a minor one, I know that there different scales that could be used the get the intervals change because of what is technically several key changes. Over A minor chord (i) you could use A pentatonic minor, A dorian and A natural minor. A Phrygian’s b2 would feel too dissonant. Over D minor chord (iv) you could use A natural minor, or D pentatonic minor to emphasise more intervals in the chord. Over the E minor chord (v) you could use E pentatonic minor, or A natural minor for the same reason. B pentatonic minor would have emphasised B minor slightly, then go back to A minor on the iv and i chords. Of course there could be some use of blue notes (b5) used as passing notes.
Next, while playing over a major blues, if the chords are all dominant sevenths in C. Over C7 (I) you could use some intervals in C mixolydian with pentatonic minor/major with passing notes (b3 and b5). Over F7 (IV) you could use C pentatonic minor (with an added major 6th interval) to highly emphasise the 3rd flattening. Over E7 (V7) you could use B pentatonic minor and B dorian, and F# pentatonic minor as these scales help suggest the chord changes.