Hi Hector,
Yes, you can delete the elastic pool and still have the ability to restore deleted databases using Long Term Retention backups, so long as the backups are within their retention period. You could even delete the logical SQL Server and still be able to restore LTR databases, however, it is more difficult [with SQL Server deleted] since you can't use GUI interface.
Please see screenshot of relevant excerpt from documentation article:
In addition to viewing available LTR backups in graphical interface, you may run command similar to below in Azure Cloud Shell:
az sql db ltr-backup list --location eastus
Please click Accept Answer and upvote if the above was helpful.
Thanks.
-TP