I already know native Spanish and still refuse to read in that, because the writing is terrible ò_ó. Mispellings and inconsistencies are all over the place. Too clear that whoever is doing it it's a second-hand translation English-Spanish, instead of Japanese-Spanish (or Korean, Chinese, whatever).
So even if you know Spanish, I still wouldn't recommend it.
Yah for this series theres a bunch of typos but it is understandable and above the level of MTL on some other series posted here. For a while they were like 20 chapters ahead for secretary jin.
As for spanish groups in general, as someone that reads chinese webnovels via MTL it aint that bad lol. Also the only way I could find the behind the relationship novel was through a spanish translation so...good for em lol. They even had the sidestory.
Spanish translations are a bit further ahead for anyone that can read that