This question was already asked but I want more recent information.
You can now.
In the post game activity the Infinite ZA Royale, after completing 15 reward matches, the player will be awarded with Eternal flower Floette and the Mega Stone Floettite.
In the aftermath, AZ quietly passes away, leaving Urbain/Taunie to take ownership of Floette and use her against the player in their 15th Infinite Z-A Royale reward. After the match, they give Floette and the Floettite to the player due to becoming the new CEO of Quasartico Inc. in Jett's place. In Pokémon Legends: Z-A, Eternal Flower Floette was finally made obtainable, being obtained after defeating Urbain/Taunie in the 15th Infinite Z-A Royale match after the credits.
In the aftermath, AZ quietly passes away, leaving Urbain/Taunie to take ownership of Floette and use her against the player in their 15th Infinite Z-A Royale reward. After the match, they give Floette and the Floettite to the player due to becoming the new CEO of Quasartico Inc. in Jett's place.
In Pokémon Legends: Z-A, Eternal Flower Floette was finally made obtainable, being obtained after defeating Urbain/Taunie in the 15th Infinite Z-A Royale match after the credits.
Source
Nope, it hasn't been officially released yet.
Source: I check Serebii every other day and I would have seen it
