This game has was planned to be released for the Nintendo Wii U but it was cancelled, however I am including this info for this game mainly for archiving purposes since I have found info about this game that says that it has falsely states that it has been released for the Wii U.
Below a list of all in-game weapons and their locations:
Weapon Hudson's pulse rifle: Location level mission 5, find the elevator, ride it up to meet with O'Neal, and get your weapons again. On this floor, search the offices to find the pulse rifle.
Weapon Frost's flamethrower: Location level mission 10, during the objective to destroy the third AA gun, find a container with a rocket launcher inside. Search that container further to find the flamethrower.
Weapon Gorman's pistol: Location level mission 4, while exploring the tunnels with O'Neal you will be stopped by a door that must be sliced open. Leave O'Neal waiting beside the door and follow the path to the left of him. There is a table with the pistol at the base of some steps.
Weapon Hicks' shotgun: Location level mission 1, explore the gravity well with O'Neal and reach the top floor, where several aliens will attack. Kill them then search the nearby rooms and catch up with O'Neal. After you are reunited,defend O'Neal from alien attacks while the door is opened. Searcg the side rooms on this floor to find armor and the shotgun.
Weapon Vasquez's pistol: Location level mission 9, turn left as you enter the interior of Hadley's Hope. Search the path until finding a room that contains armor and the pistol.
Weapon Vasquez's smart gun: Location level mission 6, you will enter an area full of shipping containers while on your way outside with O'Neal and Bella. Fight through the soldiers then go down the stairs to a garage where aliens and soldiers will enter through the open doors. Clear them out, then search the pallets stacked against the wall to find the smart gun.
Controlling the powerloader in level 4
When attacking the alien with the powerloader, be patient. Use the controls as if you were boxing by jabbing, moving away, then jabbing again. Do not rush the fight.
Huge donut in Mission 6
When you reach the "For Bella" mission in level 6 until you get the "Find a way into the Weyland-Yutani Facility to save Bella" objective. No go upstairs till you see the door, and exit the interior to enter a rocky exterior area with lava flowing down a cliff to your right. Run partway up the path ahead and look to the right across the chasm with a scoped weapon to find a box of donuts. Shoot them and they will disappear. Then, look to where your teammates are waiting to see a giant donut appear uphill. It will roll down, launch off the cliff, and explode in the lava.
Alien ship pilot holographic space battle level 8
When you reach the "Rampart" mission until you encounter the pilot of the alien ship, as featured in the Alien movie. Shoot bullets into its skull until a holographic space battle begins playing over its head.
In-Game Sonic 3 And Knuckles
When you reach the "For Bella" mission until after you drop down through some debris. Now Look inside the locker next to the sentry gun and you will find 3 spheres that resemble like the special stage symbols from Sonic 3 And Knuckles.