It may seem counter-intuitive, but play teaches our kids an enormous amount about emotional regulation--and how to identify the emotions they have.
After all, it helps to know what you've got before you try to regulate it!
Here's a great example from the wonderful Dr. Larry Cohen, author of Playful Parenting, The Opposite of Worry, and other great books.
Most children bring everything important in their lives into the play zone, and feelings are very important to them. One thing children are learning is the connection between an inner feeling and the expression of that feeling. Games that play with a variety of feelings are great for developing this awareness. A mother from the UK shared this game that her son invented at the dinner table:
"I wanted to share a silly and funny game my 8 year old made up last week over dinner. We were eating nicely together, when he suddenly said, "Everybody look at Dad nervously." We did, and exploded in laughter. We then took it in turn to look at someone laughingly, lovingly, jumpily... and had a lovely time.
It was great to reconnect, and very very loving too!"