I'm not sure why the code would work in Perl 5.28 as given, but for your problem see the Module Options of Win32::OLE. The new syntax to use is

use Win32::OLE;
Win32::OLE->Options(CP => Win32::OLE::CP_UTF8);
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Alternatively, you can make the CP_UTF8 constant known by importing it explicitly from Win32::OLE:

use Win32::OLE 'CP_UTF8';
Win32::OLE->Options(CP => CP_UTF8);
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