There are different EWI fingerings but the general idea is that standard saxophone fingerings will work, and some other that are not working on a real sax will also work. In my experience, palm keys for the right hand will move the output a certain number of semi tones higher or lower on every notes whereas it only works for some on a real sax. For instance, the top right hand palm key will add a semi tone on every note and not only on the top F.
Another one is to press one or several fingers of the right hand while not all fingers of left hand are pressed, which should lower the sound by half a semi tone. Try non standard things which seem logical ;).
Edit: page 22 of the user manual ( https://www.akaipro.com/ewi-solo ) of your EWI is describing the EWI fingerings.
As it is not bound by acoustics, EWI fingerings should be more practical as you have more different combinations for every notes. Their use or not depends if you see the EWI as a real instrument or as a silent practice of saxophone. For the latter, you should probably stick to sax fingerings. Also, sometimes playing with EWI fingerings can be annoying as it is "too" sensitive: if you slightly touch a key that you did not want to it might produce an unwanted sound. With saxophone fingerings, only valid fingerings will be taken into account which can help limit the amount of unwanted note the instrument is producing.