When creating a new application in the API Hub, using French accents (or any non-English characters) in the application's name, the characters get corrupted after it is saved. Looking back at the Application Name, it shows badly encoded characters.
API Portal 5.1 (non-customized API Hub)
This is a known defect. The fix will be included in the next on-prem release (Portal 5.1.2). The ETA for 5.1.2 is tentatively mid-October.