Since PES 2018 is an older title, official digital sales may have been delisted on platforms like Steam in favor of newer eFootball titles. However, you have safer alternatives than "highly compressed" links:
Pro Evolution Soccer (PES) 2018 is widely regarded as one of the most balanced entries in the franchise, especially for PC players who received a version graphically identical to the PS4 and Xbox One for the first time . While the original installation requires , highly compressed "repacks" can reduce the initial download size to as little as 8.9 GB . Highly Compressed Repack Details pes 2018 highly compressed for pc link