What, this doesn't cover it?

use Params::Validate;
Params::Validate::validate_options(
    normalize_keys => sub { map { local $_ = uc; s/^-//; $_ } @_ }
);
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The mistake Params::Validate makes is that it doesn't allow you to create what your simple case is.

That's not quite true. There is the validation_options function, which sets per-package defaults.

Params::Validate::validation_options( 
    normalize_keys => sub { $_[0] =~ s/^-//; lc $_[0] }
);
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You can also define parameter specs up front and re-use them. (Or put them in a config file/module for reuse across an app.)

my %specs_for = (
    foo =>
      # specify a type
      { type => ARRAYREF },

    bar =>
      # specify an interface
      { can => [ 'print', 'flush', 'frobnicate' ] },

    baz =>
      { type => SCALAR,   # a scalar ...
        # ... that is a plain integer ...
        regex => qr/^\d+$/,
        callbacks =>
        { # ... and smaller than 90
          'less than 90' => sub { shift() < 90 },
      },
);

sub wibble {
    my %args = validate( @_, {
       foo => $specs_for{foo},
       bar => $specs_for{baz},
    });
   # ...
}
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So with very little up-front work, you can create re-usable parameter validation specs with a preset default case.