Will do a proper PS4 OF tutorial when I'm home tonight but off the top of my head here are the basics (could change):
What you need
A USB stick with at least 2GB space
An option file (e.g. PESUniverse, PESWorld, WEHK)
The day one Live Update
PS4
1. Download your option file of choice and unzip it.
2. On your USB stick create a folder called WEPES. Inside that folder copy all folders unzipped from the option file
4. Plug the USB into your PS4 and start PES
5. From the main menu go to Extras > Live Data Update and install the day one update (this is important, otherwise transfers won't be current).
5. Go to Edit mode > Data Management > Import teams
6. Select all teams that appear, leave all options as default and press Import. Go and make a cuppa and wait for about 10 minutes until the automatic import is done.
7. Now choose Data Management > Import Competitions. As with teams, select all competitions and Import.
Once those have imported, that should be it. Save your edit data and play a match to check everything looks right.
PC
You have two options, a PS4 option file, or (when they're out) a PC patch.
Using an OF
1. Follow the steps above but instead of copying your WEPES folder (with the OF files inside) to a USB stick, put the folder in your Documents > Konami > Pro Evolution Soccer 2018 folder
2. Once this is done start PES and follow the instructions above from step 5 onwards
Using a patch
1. Download and unzip your patch of choice, it will be an .exe file
2. Run the .exe, point it at your PES install location (probably C:\Program Files (x86)\Steam\steamapps\common\Pro Evolution Soccer 2018)
3. Let it install, start the game and that's it.
Xbox One
Unfortunately there are no complete option files for Xbox One, nor will there be. Blame Microsoft. Their policies disallow the import of data which the game requires to be able to load user-created option files.