Yes, Sedative is definitely a goth band because most of their albums belong to the Coldwave genre, which is a core subgenre of goth music. Albums like Sedativ are examples of their goth sound.
Some of the other goth artists that are similar to them are The Cure, Molchat Doma, and Nürnberg.
Sedative is located in Russian Federation, active in 2002 — 2003. You can find more information about Sedative on their GothDB band page.