Miirym, Sentinel Wyrm

Flying, ward {2}
Whenever another nontoken Dragon you control enters, create a token that's a copy of it, except the token isn't legendary.

Alchemy Horizons: Baldur's Gate

Commander Legends: Battle for Baldur's Gate

Flying, ward {2}
Whenever another nontoken Dragon enters the battlefield under your control, create a token that's a copy of it, except the token isn't legendary if that Dragon is legendary.

Battle for Baldur's Gate Promos

If the Dragon that entered the battlefield is copying something else as the triggered ability resolves, the token will be a copy of whatever that creature is a copy of.

Miirym, Sentinel Wyrm's triggered ability copies the printed values of the Dragon that entered the battlefield. It won't copy any counters on that creature or any effects that have changed its power, toughness, types, color, and so on.