How to frame/explain that I built datasets used on several publications, but I'm not on the papers
I would cite this as work experience in your CV, without citing the publications themselves. You could mention a number of papers/projects contributed to, or mention more specifically what the projects were.

You can also see the advice on this somewhat related question: Should I explicitly remind people to include my name in the acknowledgement?

There, someone is asking about how to make sure they get properly acknowledged, but several answers and comments point out that acknowledgements aren't really cited as acknowledged papers. I'm not sure whether you are mentioned in acknowledgements in the papers you refer to, but whether you are or not the advice there would agree with mine.

Adding from @Buffy's comment, if you think this work is particularly important to your job (for example, if you are applying to a position where you will be working with datasets outside of your field and want to emphasize the breadth of your understanding) it may be appropriate to get a letter of recommendation from your collaborators.