You should be able to keep Crystalline Conflict rank rewards after changing servers
I climbed through the rank's during the new Crystalline Conflict season when it first came out and got to Crystal rank within the first month. I was happy with Crystal rank because I knew I wouldn't be able to compete for top 100. However, I recently decided to change my home world so I could join a friends FC and participate in a Ceremony of Eternal Bonding. I read that I would lose the CC rank when I transferred but the rank itself didn't really mater to me. However, I don't see a reason why I shouldn't be able to get the rewards associated for having obtained the rank so I sent in a ticket to ask if this was a feature or if there was interest for it. The support team got back to me and told me to make a post here so someone on the dev team could take a look at it and consider if it was worthwhile.