Try to let the club sit loosely in your fingers at address. Overly loose to keep the tension out of your arms and grip. Tighten a little when you swing but this will help.
I also try to think of some of the easy swinging golfers when I swing as well. Think of Fred Couples or Monty rather than Bryson or Rory.
I have had tennis elbow previously through squeezing the life out of clubs so this was forced upon me. It is surprising how much better and further you hit it when relaxed. It is an ongoing battle but well worth the effort.
Once had a brilliant and relaxing body massage very shortly before teeing off...I was like a string puppet in the hands of someone who doesn't know how to work one...relaxed? Just a bit...I was all over the place.
Try taking a big deep breathe in while setting up then exhaling just before and during your swing. If you're tense you could be holding your breathe during your swing making the tension worse. Or alternatively try fully exhaling before you swing.
That might be true at address, but I think the idea is that if you hover and have a bit of waggle (think Jason Dufner) you don’t then tense up when the backswing starts, whereas if super relaxed over the ball with the club head on the ground, the first move is to grab the handle tight which undoes all of that good work.
Personally, I don’t think you want to be tension free. You want the right amount of tension applied in the right way. Your arms shouldn’t be like a piece of string afterall! It’s probably a feeling for people that are too armsy in their backswing who need to feel their arms more relaxed with the body driving the swing.