We started to build this out in Microsoft Teams.  We have a Team called Knowledge Hub. There's a subchannel for case studies because they may cross multiple areas.  Then each center of excellence has it's own subchannel.  Our testing has stalled a bit as other projects have taken priority.  One challenge we have run into is when things overlap.  For example, information might be relevant to two COEs, but we don't want to save it two separate places.  We'd rather have it live one place and link to it.  Similarly, with training. We want that to live within our training system, but if you go to the COE you should be able to easily see what's available.

We use a tool to do this - it's called Communifier (but we branded it for internal purposes).  It's our company intranet where everything is housed and it's very searchable and user friendly.  Has helped everyone share info and find it easier.  Also had cool functionality to search on people to get to know more about your team, etc.  I'm happy to take you through a demo, if you're interested in seeing how we apply it. 

Link here.