Thank you so much!
Actually today I did some camera tests and the wireless did not work very well, the signal was very low and I had to put the gain level on the camera super high, which has no preamps, so I decided to throw a direct XLR line from the mixer to the lemo adapter. . It worked fine, it just did not give me the independence that I wanted, but the gain in the Alexa was on 0 and I just went up the mixer's output.
Another question, in mixpre 6 can only change the frame rate by connecting it to the camera with an HDMI or Aux? There is no other way?