The answer to the same would be both Saonel and Pirina.
We don't know for sure as to which of the two is stronger as they fought as a team more or less. However, I think it's fair to assume they are equally strong as superior to Picollo in strength. There might have been a couple of instances or statements made in the episode where Picollo might have appeared to be stronger than the two, which mustn't be confused with.
Here is a list of my supporting arguments: (Please Note: We don't see Saonel and Pirina fighting at full power in their first match against Picollo which is why I'm going to only make reference to the second episode they fought (Episode 118).
Once Picollo fires multiple Ki Blasts at Pirina, he is complete unfazed by it and pushes back Picollo with ease. We see Picollo struggling to push back Pirina's hand with both his hands, while Pirana doesn't even seem to be trying.Picollo is terrified of their strength as he senses a lot of absorbed namekians.Gohan turns Ultimate Gohan to save Picollo. Also note that despite Gohan training for a brief period, based on the recent episodes, I think it is safe to assume that Ultimate Gohan is definitely significantly stronger than he was during the Buu arc. He's most definitely stronger than Super Saiyan God Goku and around the same level as Android 17 who is very powerful indeed.Gohan fights at full power and seems to be doing very well. However, what made Pirina and Saonel a lot more powerful was their teamwork and combinations.Gohan also stated that since the two of them were very strong, they would be able to tank the Special Beam Cannon which is more of a killing move.We see Pirina tank the first attack which shocked Picollo. An argument might be made that Picollo didn't charge the attack enough. However, he did have a decent amount of time to charge the attack.Making a reference to an old nostalgic moment in the Dragon Ball Z, where Raditz fought Goku and Picollo, we see Raditz impressed by the attack the first time around when it shatters his armour and barely dodges it. The second time around it was strong enough to both kill him and Goku. I'm not stating that this attack is unblockable. Some of the high tier fighters like Goku, Vegeta and obviously the God tier characters like Jiren wouldn't have any trouble. We see Jiren even block Hit's killing shockwave which was strong enough to almost kill SSJB Goku in one shot.In the end, it was obviously because of Picollo's attack which gave Universe 7 the win and one of the two Namekians after getting hit by the special beam cannon said "So that's the true power of a Universe 7 Namekian". Many might assume this implied that Picollo was stronger. However, this was just a remark made on the powerful attack which Picollo had enough time to charge his attack without engaging in battle. This can be compared to Goku and Vegeta's beam struggle with Koichierator and Gohan's attack after. Goku and Vegeta didn't give it their all and didn't charge up their attack enough while Gohan charged his attack enough and his beam attack was stronger than the combined attack of Vegeta and Goku, which again doesn't imply Gohan being superior in strength to the two.
Hence if it wasn't for Gohan and Picollo had to face a Namekian by himself, I would say Picollo wouldn't stand a chance.
Images supporting the arguments made.