To provide a thorough answer to your question, some context is necessary. Eutropius was a Roman historian who wrote a concise Latin history known as the "Breviarium ab Urbe Condita." This work was later translated into Greek by a translator named Paeanius.

However, the use of Paeanius’s translation specifically by 5th-century Greek writers is not well-documented, as much of classical literature and specific uses over time are difficult to trace directly to specific writers without explicit references. The task of identifying specific 5th-century Greek writers who used Paeanius's translation is challenging due to the scarcity of detailed records from that period regarding secondary use of texts.

Scholars primarily look for references in surviving manuscripts, citations by later historians, or mentions in scholia (ancient marginalia or commentaries). If there are any more specific historical records or studies detailing such references, they are typically found in specialized academic research.

If you're particularly interested in tracing this line of historical inquiry, I suggest consulting academic works or papers related to ancient texts’ transmission and use. Libraries with strong classical studies collections or university departments specializing in classics may provide more in-depth resources and insights.