We are looking to copy all the data from one AS profile to another, however we don't see an option to copy the same datasource key value instead we can only create a new IQ datasource with a new value.
The main issue is we have only one website and a single IQ profile linked to it, which is rendering the data using the Tealium Collect tag to the first AS profile.
Each server-side profile is its own instance, so there is not a way to copy the keys between profiles. The keys are randomly generated when a datasource is created. With separate server-side profiles, all visitor profiles are also separate, and those cannot be copied between profiles (nor can database tables, as each server-side profile has its own database and store files if those products are in use). You can think of each server-side profile as a bucket, and the data cannot go between buckets, but stays in its own bucket.
In this case, you'll need to use the key generated in the new profile when sending data into the new profile.