For information I now have both as well.
Having recently spoken to customer services regarding the "Lithium-Ion Battery earth plat" they could not find any information on this. They suggested it could be an error or could be as mentioned in other posts that the recall may have gone out too early, and more information will follow. I also discovered that this particular recall was also mentioned in EV forums in Italy and France, but no other information other than a number of customers have had the message.
However customer services mentioned to me the "Intelligent Emergency braking" recall and they suggested that if at the dealer they queried it to mention "E news P9327" and its covered by Nissan.
My vehicle is currently at dealer having the issue with the "clicking sound" coming from the front wheel hubs, which they have diagnosed and are currently doing the required remedy. At the same time they will look at the Intelligent emergency braking recall, but they can not currently look at the Lithium-Ion Battery Earth plat issue as no one seems to be able to confirm what this relates to.
The dealer has loaned me a new 2019 Leaf whilst mine is repaired, so thats very good. The larger screen is definitely an improvement and much more responsive, and I also like the LED headlights.
(On a funny note, the French and Italian sites mention the Lithium-Ion issue, but some seem to mention in translation that the Earth is flat, not the Earth Plat !!!)