General opposite:
* Perezoso/a (lazy): This is the most direct opposite of "hardworking" in terms of effort and diligence.
Other options depending on the context:
* Indolente (indolent): This implies a lack of willingness to work or make an effort.
* Desidioso/a (sluggish): This suggests a lack of energy or enthusiasm for work.
* Negligente (negligent): This emphasizes a lack of care or attention to work responsibilities.
* Holgazán/a (loafer): This describes someone who avoids work and spends their time doing nothing.
It's important to choose the most appropriate word based on the specific situation and nuance you want to convey.
For example, if you are talking about someone who is simply unwilling to put in the effort, "perezoso/a" might be the best choice. However, if you are talking about someone who is careless and doesn't take their work seriously, "negligente" might be a better option.