Setting up saving in UE4 takes about 5 minutes but the variables to save and load have to be designed ideally in the beginning of development. It's really simple for anyone who knows blueprints.
Here is the tutorial I used to understand and implement saving in my games:
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If the creator of the game can't do it himself he should hire a programmer to implement it immediately, since the longer you go without it the more work and cost it will create in the end
also his patreons are literally paying for the game lmao