How to transfer Apple Watch to my daughter?

To unpair and erase watch and remove Activation Lock

From a web browser,sign in to iCloud.com with your Apple ID.

Go to Find iPhone.

Click All Devices at the top of the screen.

Click your Apple Watch.

Click Erase [device]. Select Next until the device is erased.

Click Remove from Account.

Then;

Set up and pair Apple Watch

You need to enter the Apple ID and password that was last used with the watch.

Then you can set it up with her iPhone.

If you don't know what apple ID e****@icloud.com is(if it is not yours)

To remove the activation lock you can either remove it with the correct Apple id and password

Or if you are unable to do so, and you have proof of purchase, you can apply for Apple to remove the activation lock

See this guide:

How to remove Activation Lock - Apple Support

The step to remove without knowing the Apple ID is under Start a support request

then "Get started" on the next page

Here is the direct link:

https://al-support.apple.com/#/additional-support

Good luck!

See here - What to do before you sell, give away, or trade in your Apple Watch, or buy one from someone else - Apple Support