@Azurebat That's referring to a cosmetic item Seer has equipped on their banner card. Some of the errors I saw were "seer/legendary_02", "seer/epic_v23_gala01", "seer/epic_v23voidsinister01", and "seer/epic_v22_magicgoth01".
The gala one is from the 4th picture, which is reffering to the "Moth to the Spotlight" banner card. (gcard means its the banner frame / banner background), while magicgoth is from the 3rd picture, and its the green ghost background that my random teammate has equipped on the right of the screenshot. As for the legendary one, it has to be the second legendary that was released when Seer was dropped as it says 02, while the last one is from this current battle pass, as there wasn't any void backgrounds for Seer until this season.
For you, you said you saw "common_01" and "common_script_19". The 01 should be Seer's default skin, as for the script, no clue what its referring to, maybe an animation or a holospray.
@Simbachippie Any instance of Seer's banner card, from what I can tell will crash the game. It happens when selecting Seer, looting a Seer deathbox, and I'm guessing when he pops up on the banner frames around the map as I've crashed just by shooting at a Valkyrie and then running away, (first screenshot), or running away from an Octane, (sixth screenshot).
@EA_Mari That's awesome that its getting fixed. Thanks for letting us know!