Lemme see if I can do some math and dust off my lore here. By default, Halo's technology is higher tiered than anything in Mass Effect all the way up to the Reapers, which means that Krogan armour or shielding won't mean much to Brutes. Krogans have the bonus of having dual organs for just about everything, and being notably adaptable to radiation, along with boasting blood rage, which is essentially a beserk adrenaline state when near death that nulls pain. At best, their natural strength probably puts them able to lift somewhere around 800 pounds, up to 1000, with relative, albeit slow ease. Brutes, likewise probably have a few secondary organs like hearts to make up for their weight and height, and boasting thick hide like skin, and, like krogans, extreme durability, being able to withstand a full clip of assault rifle fire at point blank wearing no armour, and still being able to move and fight. Like Krogans, Brutes also go beserk, likely growing less aware of pain and having an adrenaline spike that not only gives them a boost in strength but also speed. Brutes are capable of easily manhandling Spartans, who, in most cases, weigh on average up to 1 ton in their armour, giving them a slight advantage in strength and speed over Krogan. Now, when it comes down to biotics, again, Mass Effect's biotic abilities are mathematically defined. Most abilities like throw, or lift, anything capable of moving or impacting, hit with about the force of 1 ton at the very maximum. It's noted that lift would not be able to lift a Spartan up in their armour, and Brutes are significantly heavier. If I had to guess, most biotics used on Brutes wouldn't send them flying like a human target. It might stagger them at best. Personally, I think it's a close one. A really close one. Brutes have Krogans beat for physical strength and speed, most of all, a huge gap in speed, with Brutes being able to jump several meters into the air and being able to cover ground much faster than a Krogan could on foot. Like I said. I think it's close as shit here. But Moonbabies have just a slightly higher edge with their technology tier in terms of armour and shielding, their speed and strength. I'd give it to the moonbabies.

Brutes are likely to be stronger and with more agility. Krogans are tanks but that's their only advantage in this fight.

Proof of why krogans would destroy the brutes. Note: This is only one krogan

Brutes. Is this with weapons or without? Because Tartarus and all brutes destroy everything with Gravity Hammers

Krogans are weak and puny compared to brutes

I've never played mass effect so I'm gonna need some info before I can vote.

Krogans have natural armor capable of stopping impact based weaponry. They have extremely high strength and a moderate amount of agility. They can be psychic and they do not tire. [spoiler]plus 4 testicles[/spoiler]

I want to say Krogans, but in the same sense, I don't know. Krogans seem to be a little clunkier, and less agile than the Brutes. Tough call.