If your question is whether to cite the original or the reprint, that is a subjective matter. It depends on whether the article has simply been reprinted or whether the author has updated it.

For articles reprinted in series such as Variorum Collected Studies, the chapters are normally printed with the original pagination, allowing one to cite the chapter in the same way as the original journal article (usually they print the original publication details after the table of contents). This was useful in the days before journal articles were widely available online. These days, it is usually easier to track down an electronic copy of the journal article than the book.

I usually only cite a collection of reprints if the original journal is difficult to obtain; but some instructors and publishers insist on citing both. It is most common to do this only in the bibliography. The Chicago Manual of Style, sect. 14.16, doesn't address this exact situation, but implies something like this:

Houts, Elisabeth M. C. van. ‘Women and the Writing of History in the Early Middle Ages: The Case of Abbess Matilda of Essen and Aethelweard’. Early Medieval Europe 1, no. 1 (1992): 53–68. https://doi.org/10.1111/j.1468-0254.1992.tb00004.x. Reprint, chap. 14 in History and Family Traditions in England and the Continent, 1000–1200. Variorum Collected Studies. Ashgate, 1999. https://doi.org/10.4324/9781003555797-19.

To obtain this, add a references: Reprint, ⟨...⟩ line to the Extra field, which allows you to append any text to the end of a bibliography entry. Note that this currently only works in APA, Chicago, MHRA, MLA, and New Hart's Rules. Here is that example encoded in Zotero:

https://www.zotero.org/groups/2205533/items/8R3P7TK9

If you choose instead to cite the reprint independently, you'll need to use the chapter-number variable in the Extra field, since the book's pagination is not continuous:

https://www.zotero.org/groups/2205533/items/SH53NY6F

If the author has revised the article extensively, then it is more common to cite the later version even if it is harder to access than the original. This is usually up to your judgement, and not something for which most style manuals have a hard rule. In this case, one would probably use the revised version as the main entry, as in example 11 of the APA Manual:

Shore, M. F. (2014). Marking time in the land of plenty: Reflections on mental health in the United States. American Journal of Orthopsychiatry, 84(6), 611–618. https://doi.org/10.1037/h0100165 (Reprinted from ‘Marking time in the land of plenty: Reflections on mental health in the United States,’ 1981, American Journal of Orthopsychiatry, 51[3], 391-402, https://doi.org/10.1111/j.1939-0025.1981.tb01388.x)

Encoded in Zotero:

https://www.zotero.org/groups/2205533/items/SLFZFACR