The content is really great. Although this suggestion may not be possible perhaps due to limitations of the site (I know nothing about web coding, correct me if I'm wrong):
It will be great if there is some sort of toggle to remove mewtwo as an option due to the inaccessibility point. This sort of applies to the other guides as well...listing Mewtwo as a mewtwo counter is more than justified in the sims, but doesn't exactly help if one doesn't have M2 to the begin with. Sites like pogomoves rank DPS with an on/off toggle for legendaries and they mark legacy moves in red.
On that note it will be great to have a toggle on/off for legacy movesets- the inclusion of a RT Omastar in the scyther guide is kinda paradoxical- if you have been playing since the RT Omastar age you wouldn't be using this scyther guide, and if you need to properly read the guide to solo scyther, you wouldn't have a RT Omastar.
Not that WG/RS Omastar can't beat Scyther (even WG HP can beat it probably lol)