Updating an Apple Watch
How can you update Apple Watch 4 using an iPhone 6
How can you update Apple Watch 4 using an iPhone 6
No, you cannot. Upgrading the Watch requires iOS 13, and the iPhone 6 does not support iOS 13. You will need an iPhone 6s or above.
No, you cannot. Upgrading the Watch requires iOS 13, and the iPhone 6 does not support iOS 13. You will need an iPhone 6s or above.
And if you find a way to upgrade to watchOS 6, your Apple Watch will no longer pair with your iPhone 6
Updating an Apple Watch