Having your other post in mind I misread your question, sorry.

you don't want to operate on an array but a code-block

Would you accept something like the following as sufficiently equivalent?

sub qre(&;@) {
  my $block = shift;
  my $str = $block->(@_);
  return qr/$str/;
}
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(not tested)

udpate

some functional code:

use Data::Dump;

sub qre(&;@) {
  my $block = shift;
  my $str = $block->(@_);
  return qr/$str/;
}

sub ored {
   return join '|', map {quotemeta} @_
}

sub oredraw {
   return join '|', @_
}

my @strings = qw/. | %/ ;


dd qre {join '|', map {quotemeta} @strings };

dd qre \&ored, @strings;

dd qre \&oredraw, @strings;
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