My take would be that only, as usual, the lawyers would gain on this.
1. Knockoffs are usually horrible, rough, weak, fragile.
2. You bet that DJI would kill your warranty most snappy if they even found out that you even owned any knockoffs. Yes they would find out.
3. propeller design is a section of every manufacturer of air vehicles. Boeing has an entire section of hundreds of employees. How long did it take the soviets to find out that independent tail sections were necessary for mach flight? They actually stole the design study before they knew. So they never figured it out themselves, even though the us was sonic through many designs. When did wing edges finally change for efficiency?
4. It could be done, but only the Edison way.