So if you’d like some real advice on the team, I can provide some.dia-buff-treei like my teams to be unexpected so enjoy
Diancie-Mega @ Diancite
Ability: Magic Bounce
EVs: 4 HP / 252 Atk / 252 Spe
- Diamond Storm
- Last Resort
Wobbuffet (F) @ Focus Band
Ability: Shadow Tag
EVs: 252 HP / 92 Def / 164 SpD
IVs: 0 Atk
- Mirror Coat
Xurkitree @ Choice Scarf
Ability: Beast Boost
EVs: 4 HP / 252 SpA / 252 Spe
IVs: 0 Atk
- Dazzling Gleam
- Hyper Beam
- Energy Ball
Overall, I think there’s a pretty big disconnect between your team and the 1v1 metagame, just based off the sets you’re using.
Let’s start off with your weakest member.
Wobuffet here is just a terrible Pokémon, and there’s really no way to redeem. As a concept CounterCoat isn’t bad per-se, tho it is one of the weaker strategies in 1v1 right now. For a counter and mirror coat Pokémon you can do a lot better, notably Swampert and Blastoise who offer something more than just sitting there taking hits. Focus Band as well just the worst item. It’s only a 1/10 to survive the hit which is terrible odds.
Mega Diancie is a goodish pokemon to use as it’s fast with pretty good STAB attacks, but this set misses that. Last Resort is still a terrible move in 1v1 and especially so on Mega Diancie. I’d recommend dropping the last resort for a more standard set with a full spectrum of attacks rather than Last Resort.
Xurkitree here is probably the closest to a viable set for 1v1 simply because you’re doing the least unusual thing with it. 4 attacks Scarf and Electric attackers are both good strategies. But Xurkitree is outclassed in both categories most of the time. Scarf Porygon-Z is much better thanks to its ability Adaptability and moves like Hyper Beam while Zeroara can use multiple utility moves as well as a Z move to putout that damage.
I recommend using some of the sample teams from the previous thread before trying to build again. You’ll have a lot more success with more standard sets.
I also recommend checking out these threads to get a better sense of what’s good and what’s not in 1v1
You can also join us and ask for advice in the 1v1 room on Pokémon Showdown! and on our discord https://discord.gg/ye28pKx