Pokémon: can Haunter evolve without trading?

Can Haunter evolve without trading?
No, Haunter cannot evolve without a trade. Like other Pokémon of the same type, Haunter’s evolution requires a trade with another player to be triggered. Currently, there is no alternative method available to evolve Haunter without going through this process.
Does Haunter’s evolution require a trade?
Yes. Trading is an essential condition to evolve Haunter in all the versions of the game where it appears. Whether in older games like Pokémon Red and Blue, or in more recent versions like Pokémon Sword and Shield, Haunter can only evolve after being traded with another player.
Is it possible to bypass the trade to evolve Haunter?
No, there is currently no official method to bypass trading in order to evolve Haunter. Unlike some Pokémon that have received alternative evolution methods in Pokémon Legends: Arceus or other recent installments, Haunter remains tied to the trading mechanic for its evolution.
Is there an item that would allow Haunter to evolve without trading?
No. There is no item like a “Link Cable” or an evolutionary stone that allows Haunter to evolve without trading. This limitation is intentional and is an integral part of the game mechanics for certain Pokémon like Haunter.
Conclusion: Is it necessary to trade Haunter to make it evolve?
Yes, unequivocally. If you want to evolve Haunter, you will need to trade it with another player. Currently, no other method allows you to trigger its evolution in the official games.