I’ve read many theories on this and most believe that Luffy’s abilities will turn the environment into rubber.
This theory of course comes from that fact that we’ve seen 2 Paramecia Devil Fruit Users whose powers have been “Awakened” in the same way. Doflamingo being able to even turn his surroundings into string and Katakuri being able to transform inorganic material into mochi.
Now Katakuri is a special paramecia where he is mochi and can produce it but still he produces it where Luffy doesn’t produce rubber, he is just made of rubber which is a point to this theory that Luffy’s awakening is different because he doesn’t produce his ability. My theory is that Luffy will have the ability of resistance and shock absorption as the way of affecting the environment and objects. You will not physically see the environment and objects turning into rubber but you will feel these effects that rubber can produce on the environment and objects. Think of the resistant rubber bands you use for working out as one way of looking at these abilities.
“Resistance and shock absorption” is the Gomu Gomu no Mi true power. Imagine trying to swing a punch but something is forcibly holding you back from swinging or at least like maybe against Kaido, decrease the power of the punch or kick in which causes little to no damage then using shock absorption to cancel the attack. I see Luffy being able to control areas in which he could place these abilities to i.e body parts, objects, atmosphere etc and use both resistance and shock absorption at the same time to slow down a punch or kick and to nullify the attack.This could also be applied to devil fruit abilities as well. Imagine Blackbeard using the Gura Gura no Mi abilities as he cracks the air. Luffy could use awakening to create basically that invisible rubber(resistance) to the area of the cracked air and nullify the ability (shock absorption). Think of these examples of like the fight between Nomu and All Might from My Hero Academia.
Let’s go further. Combo this ability with what we suspect Luffy’s now future sight and you can see how he will be able to dodge and defend attacks against Yonkos. First he will use his future sight to see a little into the future to see where he is going to get attack and to see what body part or ability that will be used against him. Now that he knows where the attack takes place, he will know where to place his awakening to the correct body part or object and area to slow and nullify the attack. This seems legit if Luffy gonna beat the strongest creature.
*Theory by RoronoaDanny