Due to the Ultra Beast factor of Buzzwole-GX, the following list might prove to be a way to make up for the loss of all those cards by rotation AND perhaps maintain Buzzwole's dominance, but although I won't bet on that just yet, if someone has such an idea along the lines of this list, it will be something to watch out for, in case it proves to be a good rotation work-around:
****** Pokémon Trading Card Game Deck List ******
##Pokémon - 17
* 2 Dawn Wings Necrozma-GX UPR 63
* 1 Diancie {*} FLI 74
* 2 Buzzwole-GX CRI 57
* 4 Rowlet SUM 9
* 2 Dartrix SUM 10
* 4 Decidueye-GX SUM 12
* 2 Tapu Lele-GX GRI 137
##Trainer Cards - 33
* 1 Energy Recycler GRI 123
* 1 Rescue Stretcher GRI 130
* 3 Beast Ring FLI 102
* 4 Rare Candy SUM 129
* 3 Altar of the Moone GRI 117
* 2 Fan Club UPR 133
* 4 Cynthia UPR 119
* 2 Field Blower GRI 125
* 3 Guzma BUS 115
* 4 Judge FLI 108
* 2 Choice Band GRI 121
* 4 Ultra Ball ROS 93
##Energy - 10
* 6 Fighting Energy
* 3 Psychic Energy
* 1 Beast Energy FLI 117
Total Cards - 60
****** Deck List Generated by the Pokémon TCG Online
www.pokemon.com/TCGO ******
^ Then again, if Decidueye-GX proves to be the way around the lack of Strong Energy post-rotation in Buzzwole decks, AND if that allows it to dominate in a similar light to what it was during Strong Energy's run in Standard, Buzzwole-GX could earn another month and a half of dominance until a new Lunala-GX, one that comes out one month after the rotation hits, becomes tourney-legal w/ an attack that deals 200 damage(before Weakness, Resistance, and other effects), to give Buzzwole a long overdue autoloss possibility...
Question: Buzzwole-GX: Next-Season Contender?
Answer: Wait until the first regional of the year, and its results: If Buzzwole-GX wins that, whether by workaround or plain, then Lunala-GX might be the one everyone is waiting for to beat Buzzwole-GX, especially after Ultra Necrozma-GX, the supposed "deck that can beat Buzzwole-GX", proved to be a flop in key situations, such as those involving opposing Fairies, those involving its bench space being cut by Sudowoodo GRI, those involving failure to draw an energy from deck by supporter or other out, forcing it to either take ability uses from 3 Malamars from FLI just to achieve a key KO vs. a stage 2 GX, or even Alolan Ninetales-GX w/ a Dumbells attached or get owned, among other examples of situations where you have to KO one GX in one turn or else your Ultra Necrozma-GX will get KO'd, so after SM8 drops in English, Ultra Necrozma-GX could see its demise as well, while Lunala-GX, as well as decks that use only Psychic energy, begin to rise...