Downgrading maven version in brew

Check current version of maven using

mvn -verison

This will give you current version and the installation path as well. In my case current version is 3.5.0 as shown below

Then search for available versions of maven using

brew search maven

This will show you all the available versions as shown below

If you want to install maven 3.0 for instance, then type

brew install maven@3.0

This will install the downgraded version and show some caveats as well

Now the next step is to unlink older maven version and then overwrite it with version you just installed

brew unlink maven
brew link --overwrite maven@3.0

Now check version of maven again. if everything went well ,then you will see that version has been downgraded.