Hi @albus d, OAuth2 client creation can now be managed from Developer tools in Lucid. The article you linked is about migrating the existing OAuth2 clients from the Lucid Admin Panel to your developer portal - this only changes where you view the clients and doesn’t impact your ability to manage them or create new clients.
Can you please confirm if you are able to create an application from your Developer portal?
Here’s our Help Center article and guide for instructions:
Second, can you please verify if either of your applications are intended for public use? Currently I can see the clients associated with your account are not published publicly, though, should still work for users internal to your Enterprise subscription.