# If you'd like to omit non-matching lines from the result; add ';d' to the end of the expression.
sed -E 's/(^|\s)(?!(?:visual)?(?:basic|studio|asp|v[bs]|c\#)\.net)(\w+)(?:\.com?\.[a-z]{2}|\.[a-z]{2,6})\b/\1\2/gi;t' <<< "site.org asp.net dsgsvgs somedomain.com sdbbdsb vb.net otherdomain.org vs.net wax.museum somesite.net vb.net micro.co.uk sdbsdbssd asp.co.uk visualbasic.co.hk ASP.net visualstudio.co.jp ddddddd visualbasic.net visual basic.net visual studio.net"
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for SED, please visit: https://www.gnu.org/software/sed/manual/html_node/The-_0022s_0022-Command.html