How can I sync different Lightroom accounts?

You can download all images from an account using this app: https://lightroom.adobe.com/lightroom-downloader You should also be able to export individual images as originals and import those in the other account if it only concerns a few images

You may find Charlie's more detailed explanation on this thread helpful:

https://community.adobe.com/t5/lightroom-ecosystem-cloud-based-discussions/how-do-i-transfer-my-library-and-presets-to-a-new-account/td-p/12410352

Thanks for replying, but my expired account is not allowing me to do anything or share.

Following Charlie's advice in this thread may help (if your expired account lets you):

https://community.adobe.com/t5/lightroom-ecosystem-cloud-based-discussions/transfert-file-from-lightroom-mobile-account-to-a-new-one/m-p/11915480

But slightly changing to: In your active account, create a shared album and invite your expired account to join it.  Make Sure the Shared Album is set to "Can Contribute"