The most direct way to bypass a block is to use a proxy site that acts as a "middleman" between your computer and the Showdown servers.
If you are looking for a or a way to bypass restricted access, this guide covers the most effective methods to get back into the battle arena. Official Pokémon Showdown Access Points pokemon showdown unblocked link
Sites like Syncios often list mirror links or embedded versions of simulators that slip through basic filters. The most direct way to bypass a block