If you are looking to hire, then my vote goes to Upwork. You can find experienced freelancers charging low money because they can't sell their skills elsewhere. In other words, they are not capable of marketing themselves for more money, so they work on platforms such as Upwork or Fiverr.
If you are looking to work, avoid freelance platforms at any cost. It is not worth anyone's time to work on platforms that take 20% of your earnings. Not to mention you will constantly battle with competition looking to charge less money to obtain more work.
Try to look for clients outside marketplaces if you are a freelancer
Where do you recommend to get clients?