I've seen video and heard stories. Anyone ever run into these two animals and they acted aggresive?

In the wild, no.
An otter in a cage trap will will make a bobcat look timid.

yes, I have had beaver come close during setting traps, really close, to close!

Beaver in a snare can jump and lung and will come at you. Otter are very fast an I am lickey I have fingers not removed after releasing one. Luckily it turned the 3/4 plywood into dust when it got its mouth under it and didn't get my fingers. Now not in a restraint I have never experienced any behavior other than flee or ignore me.

Doing an ADC job. Because of location and concerns with using 330’s I was using snares with a long extension as I found they fight less.
Was checking them before daylight and saw I’d made a catch but saw no beaver. I was standing in about 2 ft. Of water with a small bank to my left.
I heard a hissing sound very similar to a cat but more drawn out. Maybe 7-8 seconds long and just off my left ear.
I looked to my left and there was the beaver at shoulder level about 2 ft. from me on that bank.
It was the beaver that made the hissing sound.
If it had wanted it would’ve tore me up.
But it just sat there.

Beaver torpedoed out of the water at me while I was standing on the dam duck hunting. Emptied the 2 rounds of 3” #2s point blank with the SBE2. But I shot so fast, by the second round it was barely breaking the surface. Think the water absorbed most of the shot. Buddy across the little pond said it looked like a scene outta Jaws. He came out and I speared it in the face which turned it back into the water. Blood trail in the water and he never went down. Buddy finished it off with the 22-250. I shoulda made a hat outta the leftovers of the pelt. 2 years later, I’m a trapper…lol.

Just out of curiosity, what was your buddy carrying a 22-250 for?

Was standing in the water about 10 inches deep with my back to the pond...while making a foothold set...and actually got wet...from a tail slap...that scared the crap out of me...lol

Yotes, in this case, beaver. There’s a high power close by most the time……unless I’m bow/muzz hunting.

I'm surprised the surprise didn't get you to snap yourself in the trap. Once seting yote traps I had my daughter 3 at the time with me. She was about 15 feet away and squeeled I jumped and looked to see if she was safe and ok. She was and playing with frogs in a puddle. Me I had to get the trap off my hand befor I could move.

Released several otter here as we had no season then. They are mean!! becareful, bobcats are simple with a bucket......j.k

Nutria are the most dangerous mammal of the Americas for attacking me. They do not puff up and bluff you. When they come after you, they do not stop. While they would rather run or swim away from you, if they can't, they will come at you with everything that they have.

Beaver severalTimes