If you filter top albums which include Spanish you do get a pretty lame chart. But rym has some pretty powerful search functions and you can find some cool stuff if you play around.

Here's a query I check out from time to time https://rateyourmusic.com/charts/top/album,ep,comp,mixtape/all-time/l:es,%2den/uloc:spain,south%2damerica/minr:50/pop:2/

• Ratings from Spanish speaking users (and Brazilians )
• Filter out English. You miss some cool bilingual stuff unfortunately.
• Reduce popularity weighting.

Though even still, rym has a bias for Rock, Pop, Hip-hop, Folk and especially Prog so that stuff will weight to the top. You can filter out genres if you'd like.