Provided you are using the native in-line encryption provided by Windows, the only way to recover them is to obtain a copy of the original encryption keys. These are notably not based on your password/PIN (though they are encrypted by a master password secured by your login credentials). Windows provides an option to export these security keys in PKCS#12 format for backup purposes (and will usually nag you about backing them up until you either do so or explicitly turn off the nag notifications).
Without these encryption keys, there is no realistic way you can recover the file contents, as the encryption methods used are sufficiently secure to protect against most attacks.
Unfortunately, as you reinstalled Windows 10, you no longer have access to these keys unless you had previously backed them up somewhere else.