In general, it is not preferred to place Shwetambar and Digambar idols together in the same main worship space if it causes mixing of their distinct vidhi, bhakti, and tradition.

Why?

• Shwetambar murtis are usually adorned and clothed.
• Digambar murtis are traditionally nirvastra and follow a different form of worship.
• Each tradition has its own murtipuja paddhati and temple customs.

So can they be side by side?

• In a common display or respectful separate area: it may be possible if both traditions agree and proper dignity is maintained.
• In the main garbhagriha / worship altar: generally, it is better not to mix them, and instead keep them according to the temple’s own sectarian tradition.

Best Jain principle

• sampradayik maryada,
• shuddha bhavna,
• and respect for both traditions.

So the simple answer is: generally no in the main temple sanctum, but in a respectful separate arrangement it may be acceptable depending on the temple’s tradition and management.