Is it possible to quickly increase the values of the fixed Sell Price buttons, e.g. by a factor of 10 like the scale buttons?

Yes, you can do so by clicking on the “s9” button to the right of the fixed Sell Price buttons, which increases the values in the fixed Sell Price buttons by 10 times, this mode is necessary when any coin has anomalous price spikes of +30, +50, +100% and the values on the buttons are 3, 5, 10%, then you can quickly change all Sell Price button values by 10 times and not change them manually.