Hi Dustin, thank you for your attention.
After a few weeks, I have news... indeed, the IAPs refuse the association of legacy repeaters if IDS measures are applied.
Thank you for the information regarding to violation of FCC regulations. In this case we don't have any problems with that - the warehouse is on the middle of nowhere!
As you say, I also believe no such feature exists to explicit block legacy repeaters or wifi range extenders. But IDS feature solve my problem.
Thank you Dustin, take care and stay safe.
Cheers, Joao