Resident Evil 4 VR does not include unlockable modes, including the Mercenaries and Separate Ways.
In a statement sent to IGN, a Facebook spokesperson confirmed that these modes were not included in the VR version of Resident Evil 4, though did not elaborate further as to why the decision was made to cut these modes in the game. All three of these modes were available to unlock after completing Resident Evil 4's main story once.
Assignment Ada, while non-canon in the Resident Evil lore, this game mode had players controlling Ada Wong as she tries to collect samples of the plaga for Albert Wesker. The Mercenaries Mode is an arcade-style minigame with the goal is to kill enemies and rack up a high score before time runs out. Starting with Resident Evil 4's PS2 port and onwards, the game would get a third unlockable mode called SeparateWays, where you play through the entire campaign of Resident Evil 4 through Ada's perspective.
Despite the cut modes, I noted in my review of Resident Evil 4 VR that the recent re-release offers plenty of changes to gameplay and combat make it an easy recommendation for anyone that owns an Oculus Quest 2 headset.
Resident Evil 4 VR launches October 21, exclusively for the Oculus Quest 2.
Taylor is the Associate Tech Editor at IGN. You can follow her on Twitter @TayNixster.