1、 将项目projectA从仓库repoA迁移至repoB

git clone --bare  repoA
cd projectA
git push --mirror repoB

2、将原仓库repoA中某个项目project中的某分支branchX迁移至新仓库repoB

## 从原仓库repoA克隆projectA   branchX
git clone -b branchX repoA-projectA地址
cd projectA
## 确认当前分支
git branch
## 删除原仓库源
git remote remove origin
## 添加新仓库源
git remote add origin repoB地址
git push origin branchX