Workaround is to add ;

grep { ;no strict 'refs'; } qw(x);
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but that confuse Deparse :D

perl -MO=Deparse
use strict;
use warnings;
grep { ;no strict 'refs'; } qw(x);
^D
use warnings;
use strict 'refs';
grep {();} 'x';
- syntax OK
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Also works

grep { do{ no strict 'refs'; } } qw(x)
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