In my opinion Metagross/Solgaleo seems better than everyone thinks. I recently played this deck at a regionals competion and got top 16, using this deck. Many people underrate it because of its consistency but those people run 1-0 Skyla. while the deck that got me to top 16 runs a 4-3-4 line of Metagross, a 2-1 line of solgaleo, 4 rare candy, 4 ultra ball, 1 heavy ball, 2 brigette and 3 Skyla. Quite consistent in my opinion. Well here is my deck list if you are interested. if you have questions don't hesitate to ask.
Pokemon
4- Beldum
3- Metang
4- Metagross-GX
2- Cosmog
1- Solgaleo-GX
One- Magearna-EX
One- Alolan Vulpix
One Mr. Mime
2- Tapu lele
Trainers
4- N
3- Sycamore
3- Guzma
3- Skyla
2- Brigette
4- Ultra Ball
4- Rare Candy
2- Choice Band
3- Max Potion
One- super rod
Energy
9- Steel
Pokemon
4- Beldum
3- Metang
4- Metagross-GX
2- Cosmog
1- Solgaleo-GX
One- Magearna-EX
One- Alolan Vulpix
One Mr. Mime
2- Tapu lele
Trainers
4- N
3- Sycamore
3- Guzma
3- Skyla
2- Brigette
4- Ultra Ball
4- Rare Candy
2- Choice Band
3- Max Potion
One- super rod
Energy
9- Steel