Although many are understandably upset about the retcon to Sindel's past, there's little doubt many are looking forward to the Dark Empress appearing in Mortal Kombat 11. She won't be alone, however. Kombat Pack owners will also receive two cosmetics DLCs on the same day, one being the Klassic Cassie skin and the other being the Gothic Horror pack. It seems likely that it will be somewhat similar to the MK11 Halloween Masquerade skin pack, but it'll still likely have similar tones.
After all, it's not coincidence that it is releasing along Sindel, a character who has dark Gothic overtones herself, so players should expect skins associated with the grim, macabre, and eerie. It remains to be seen which characters exactly get new Mortal Kombat 11 skins, but it's possible to narrow it done some. First, Cassie Cage is out. It wouldn't make sense to give her a skin in the Gothic Horror pack and release a standalone skin at the same time.
Secondly, because they were featured in the probably similar-themed Halloween pack, this rules out Jade, Kabal, and Liu Kang. This immediate elimination still leaves several characters, but it wouldn't make a ton of sense to give dark skins to characters who themselves already have a dark background or character design like Mortal Kombat 11's Sindel. Because of this, eliminating Kollector and Noob Saibot makes some sense.
On top of that, it makes sense to eliminate characters who have received skin packs in the past (excluding standalone skins) because, thus far, Kano is the only character to appear in more than one Mortal Kombat 11 skin pack. The Klassic Arcade Ninja Skin Pack rules out the remaining ninjas like Scorpion; the Double Feature Pack rules out Sonya Blade, Johnny Cage, and Kano; and the Klassic Arcade Fight Pack rules out Jax and Kung Lao (the 3rd is also Kano).
Out of the remaining fighters, it would also make sense that characters Sindel shares a history with, even before the retcon, to receive a skin. Under this possibility, it would make sense for Shao Kahn, Kitana, and Nightwolf to get new skins. The first two simply because they are related in some manner, and MK11's Nightwolf because he sacrifices himself to defeat Sindel in the 2011 reboot.
Another possibility is that the fighters remain completely random or give certain characters more attention based on fan service. As a result, Baraka seems like a possible choice, as he recently received a new brutality based on a classic fatality. Skarlet and Shang Tsung also seem to be favorites in need of a skin, and their inclusion would likely be well received.
Considering these eliminations and possibilities, that only leaves Cetrion, D'Vorah, Erron Black, Frost, Geras, Jacqui Briggs, Kotal Kahn, and Raiden, potentially meaning they will be saved for another skin pack. Of course, this is mere speculation, so it's possible certain characters were included as possibilities or eliminated under a false presumption. Mortal Kombat 11 players will likely learn the identities of the characters in the Gothic Horror Pack, regardless, and sooner rather than later.
Mortal Kombat 11 is out now for PC, PS4, Switch, and Xbox One, with a Stadia version also in development.