Decrypt P2P WebSocket TLS Traffic

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• The P2P application has a .crt and .key file.
• The certificate is X.509 DER.
• The application communicates on a specific port.
• The application uses WebSocket to communicate with the peers.
• The IP addresses of the peers are not known before. The application aquires the IP addresses of the peers from a tracker and from other peers.
• TLS versions in use are 1.2 and 1.3.
• The keys are exchanged by Diffie-Hellman with Perfect Forward Secrecy.
• The application doesn't support the SSLKEYLOGFILE environment variable.

How to configure Wireshark (4.4.2) to decrypt TLS on the fly (like if the application would support SSLKEYLOGFILE)? If that's not possible what are potential ways forward?