Are you getting a failure for installing Crypt::Curve25519? If so see https://github.com/ajgb/crypt-curve25519/pull/11

sudo cpanm -vvv https://github.com/pyperanger/crypt-curve25519.git
sudo cpanm --look Net::SSH::Perl
perl Makefile.PL
make
make test
sudo make install
[exit from 'cpanm -look' by ctrl+d or 'exit']
sudo cpanm -vvv Net::SFTP
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