git clone https://gitee.com/oldxxx/oldxxx.git
git remote remove origin
git remote add origin https://gitee.com/newxxx/newxxx.git
git push
或
git push --set-upstream origin master
git clone --bare https://gitee.com/oldxxx/oldxxx.git
git push --mirro https://gitee.com/newxxx/newxxx.git