It will work fine, as long as you use Airtronics X-tal.
Futaba X-tal have a Negative Frequency Shifting.
I too, using 3 Futaba RXs, 2 Novak XXL (for Futaba) and only one Airtronics RX that came with M8 that I bought years ago.
I saved all my Futaba RXs, just got rid of all Futaba X-tals.
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