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Another thing I would really like to see implemented in your tool is the display of all private keys;
P2SH
SegWit P2SH
P2PKH Legacy
And any other, which is supported by the BTC protocol.
Is it possible to do this implementation?
The private key is just a number. So, no need to make a development to display all private keys. From one private key you can create P2SH, Segwit and bech32 addresses (as you mentioned in your post).
For example, let's take the 256bit number: 4890b831f6257996f56b43f49624478515a497ba8241e64df2b13e22de14fdcf
The related WIF private key for this number is KyemX2RuWDHAvGq7Fn2e8ALLQFvq5sb41kU2hi4jsej4hdjBkBF7
The corresponding legacy compressed address is: 1JX3r8HJdgkeSqGHejMp7SPKTPXn2EXXD2
The corresponding bech32 address is: bc1qcq50ue8xudrtgltzuw34k9vtexmdcg8ly0zjd5
The corresponding Segwit address is: 3C3J1coQwWx7pJBSR37YgTmhEW6SL4kQ9E
So, one private key leads to different bitcoin address types. Probably you wanted to have all types of bitcoin addresses, but not all private keys.