I was bored so I looked up everyone's Strength of Schedule or in other words i counted the combined records of players a team faced. (For example Argentina's opponents had a combined record of 8-8 not counting the games vs. Argentina themselves). Here is the list ranked from easiest to hardest:
Bangladesh: 0,25 (3-12)
Switzerland: 0,625 (5-8)
Greece: 0,75 (6-8)
South Korea: 0,75 (6-8)
United Kingdom: 0,77 (7-9)
Venezuela: 0,77 (7-9)
Mexico: 0,875 (7-8)
Africa: 1 (8-8)
Argentina: 1 (8-8)
Belgium: 1 (8-8)
Chile: 1 (8-8)
Turkey: 1 (7-7)
Asia: 1.28 (9-7)
Brazil: 1,5 (9-6)
China: 2 (10-5)
Peru: 2 (10-5)
Austria: 2,25 (9-4)
I did not count players who only played 1 game because of a substitution or ffw - which might make Austria's or Switzerland's SoS harder/easier than it shows here. Also i double checked but still might have miscounted once.
In the end it doesn't really mean much because it's just 2 games and doesn't take many things into account. Nevertheless I think it's still interesting to look at.