Is it possible for any Bitcoin exchange or Any Crypt Expert [who has expertise in cryto algorithms] to come to know that these 2 addresses are:
For bare addresses, there's no data or tag that'll link them to the HD source.Those addresses are derived from their respective public key having steps using "one-way" hashing algorithms, namely, SHA256 and RIPEMD160.
The other steps are just for checksum, address type and encoding; there's nothing to link it back even just to the public key, more so, to the extended public key.
Then, for scenarios with spent inputs where the public key is exposed, there's no way to link them to the HD source either.
Those child (public) keys are derived from the extended public/private key using another one-way method "HMAC-SHA512" with different 'index'.
It simply impossible to compute the extended private key from the public key.
Read this for more info about how HD Wallets work and how the child keys are generated: learnmeabitcoin.com/technical/hd-wallets
But that doesn't mean that your privacy is certain.
As mentioned by others, there are methods that can potentially link them together; IMO, number one is using their associated UTXOs together in a single transaction.
Second is by connecting to a public server that's "investigating" Electrum users. (not all of them does but consider your privacy compromised by using public servers)
