At least on new Samsung devices, applying wallpaper engine (or any live wallpaper) only gives you these two options:



As such, it's ?impossible? to set a live wallpaper as only a lock screen. Even if you try setting both and then change just the home screen after, the lock screen wallpaper will reset.. However, I've found a way that lets you set only a lockscreen animated wallpaper, however it won't work with any interactive wallpapers, and works with only pre-rendered ones.

So the solution concept is fairly straight-forward:

• Connect phone to wallpaper engine as usual
  
• Select the wallpaper you'd like to send, and click "Send to phone"
  
• In sending options, select "Performance" (pre-rendered)
  
• Click send
  
• Wait for your computer to generate the pre-rendered video file, and catch it before it's sent
  
• Manually copy the wallpaper video file into your phone
  
• In Android wallpaper options, select "Lock screen wallpaper", then "Choose from gallery", and then select the video file you just sent from the computer as wallpaper
  
• Done

The rest of the guide will explain how to do this all in detail.

First, find the wallpaper you'd like, make sure it's supported for Android.
After subscribing and downloading it, download the Wallpaper Engine app on your phone and follow instructions to connect it to your computer.
After following all instructions, the following button should appear under a selected wallpaper:



If it appeared, that means you've set up everything correctly, and can move on to the next steps.

Now, begins the hardest part (which isn't that difficult at all.)

First, navigate to where you have Wallpaper Engine installed. You can do this by right-clicking Wallpaper Engine in your steam library, going to properties, and clicking "Browse files".

You should then be prompted with a file explorer window like this:


In here, open the "projects" folder. Inside it, you should be able to find a "temp" folder. (If it's not there, try applying any random wallpaper to your phone first)
Inside of the "temp" folder, there should be two folders; "mobile" and "publish". If they're not there, don't worry, since we won't need them anyway.

Now, with the "temp" folder open, you should open wallpaper engine and click to send a wallpaper to your phone. The following dialog should pop up:


(Note, that this method only really works with "Scene" type wallpapers, however it's possible to do this with any wallpaper, which I might cover in a future guide.)

Here, select "Performance" and choose the settings below to your liking, but do not click "Ok" yet!

What is going to happen now, is that upon clicking "Ok", a folder is going to appear in the folder we already have open. The folder will be named "transcode". You will have to, as fast as possible, open it. Inside of it, you'll find a "wallpaper.mp4" file, which is what we need. You'll have to open the file as fast as possible in any video player program, such as VLC. If you get an error that the video can't play, try multiple times, or try different programs. Once the video has been opened in the program, we have succeeded. (the video should show nothing and just be plain empty screen) What we have just done is stopped the wallpaper file from being deleted after sending it to your phone, by opening the file in another program, which prevents any other programs from interacting with it.

Now that you've done that, follow the progress of the wallpaper being sent to your device in Wallpaper Engine. Once it has been sent, we can continue:

Close the video player window, and copy the "wallpaper.mp4" file to your phone in any way you'd like, to any folder, preferably "pictures" or any other folder in the root directory.
We now have the wallpaper.

This is the easiest part. This varies depending on what phone you have and what type of android. But now applying the wallpaper should be as easy as applying any other picture. Go to "apply wallpaper" on your phone, there you should be able to select the lock screen, and then choose to pick a photo from your gallery. In your gallery, you should be able to see the video you sent from your computer "wallpaper.mp4". Select it, and apply.