From a practical standpoint why would this happen. From a problem-solver standpoint, try this:

package Process::Data::UTF8;
sub foo { ... }
1;

package Process::Data::NonUTF8;
sub foo { ... }
1;
use utf8;
Process::Data::UTF8::foo ("string in utf8 format");
no utf8;
Process::Data::NonUTF8::foo ("string containing 8-bit character set hi
+gh chars");
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