In Jain tradition this is understood differently in Digambar and Shvetambar sanghs, and it is mostly by definition and tradition, not by a one-line “ban” sutra.

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1. Digambar tradition

• In Digambar achar‑granths (like Mulācāra etc.), an Āchārya is defined only as a nude muni (Digambar monk) with certain higher qualities and responsibilities.
• Women in this tradition are Āryikā (clothed female ascetics). Because they are not nude munis, they are not counted as “muni-sadhu” in the technical sense.
• Since the achar‑texts describe Acharya‑lakshan only for a muni, and the whole monastic hierarchy is built on that, only a muni can become Āchārya.
• Therefore, in Digambar practice, nuns do not become Āchārya. It is not usually based on a separate explicit line like “nuns cannot be Āchārya,” but on:

- the definition of a muni, - the definition of an Āchārya (head of munis), - and the separate category given to women (Āryikā).

So: in Digambar tradition, by achar‑definition and continuous practice, nuns do not become Āchārya.

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2. Shvetambar tradition

• Shvetambar Agamas and later Cheda‑sutras describe the qualifications of an Āchārya in terms of a bhikshu/sadhu (monk) – grammatically masculine – who leads other monks and nuns.
• The same texts place sādhvīs (nuns) under the authority of the Āchārya and other senior monks.
• In actual tradition across Shvetambar sects, Āchārya has always been selected from among monks, not nuns.

As far as commonly‑known Shvetambar codes go:

• There is no widely cited Agamic line explicitly phrased as “a nun cannot be Āchārya.”
• Instead, the role is defined only for monks, and nuns are given other senior titles (e.g. Mahāshramaṇi, Pramukhā etc.) but not Āchārya.

So: in Shvetambar tradition too, nuns do not become Āchārya, but this is understood from the way hierarchy and achar are framed, not from a famous single prohibition verse.

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Summary

• Digambar: By definition, only a nude muni can be Āchārya → Āryikās (nuns) do not become Āchārya.
• Shvetambar: Āchārya is described and historically appointed only from monks; nuns are always under an Āchārya and do not receive that title.

You can see a simple explanation of who can become Āchārya here