Indeed, if we want to show our citizenship, our Libernesia account is the best proof, and if that's not enough, we can design a certificate to welcome and show that the person is a member of our country, as well as let the receiver be proud of it.
However, the nature of the ID card is different: a bunch of personal data plus an identification number implies that only specific people can belong to the country, and it's like a shapeless fence that creates barriers (protectionism). Also, providing further information is personal freedom, and to have someone manage the people through this information, e.g., to give some people some permission to do something or enjoy welfare or to keep track of their actions in society. Perhaps we can analogize this situation to a sheepfold or even a shepherd, which is not in line with the purpose of our free country. Our free country is currently open to welcoming new people to join freely as members; why can we give the power to some people to issue ID cards for others? To be recognized by them? So the aforementioned "certificate" and the "ID card" differ in nature and purpose.
As for diplomacy, if people need us to prove our identity, I think getting a document to represent us and our country is necessary. The purpose of this document is to say to others that we are from this country, just like a business card. Have you ever seen others or handed out your business card to someone or hung it in front of your body to say you are a member/participant? We can use something like this as a document for diplomatic purposes. We are not affiliated with the government or National Socialism but can represent our country.
A common belonging to this community and the freedom to participate versus the governance and governed relationship: It is wonderful to figure out the difference between them. Thus, Libernesian citizenship is not the exclusive preserve of the governors but an act of community participation. We received this certificate for being community members, not for government recognition. We are a free country with a different and pioneering role than the existing ones, so there is a need to think out of the box, to be a little creative/improvemental, and certainly to change the traditional things/framework and their definition and nature to adapt to the mission of our country.
I have tried my best to explain some of my ideas and thoughts, but they may not be perfect, so I hope you can understand what I mean. Some of the more important points I want to emphasize are in bold. If you have any questions or ideas, please feel free to ask and discuss them.