If you're using yum or dnf to install packages then these come from repositories which can reside either locally or on a remote server. By default dnf sets up for accessing IBM's repositories. You can build them locally. If you have access to IBM ESS then you can download the full Linux Toolbox as an ISO. This have already prepared repodata for each repository (noarch, ppc, ppc-x.x, etc). The alternative is to use the rpm command and manually resolve the dependencies. I just did that yesterday for installing python 3.7 and only needed 10 additional packages as the target server already had some dependencies installed.
Edit:
this page on using yum on AIX should still be relevant.
------------------------------
Zaki Jääskeläinen
------------------------------