The idea of each nation which shares a common language and ethnicity should have its own state, which Europe hasn't learned to be comfortable with yet, is one of Europe's most pernicious exports to Africa.
Zimbabwe is not as multi-ethnic as some countries, but it does recognise officially at least eight small minority languages, all but one of which are more widely spoken somewhere else. That is in addition to the two major languages, Shona and Ndebele and those also are not limited to Zimbabwe. Shona is a recognised minority language in Mozambique as Ndebele is in South Africa.
But this diversity is threatened by the pressure to become «all one people» in an ethnically and culturally uniform state.
For example, in this parish there used to be one Sunday Mass in chiChewa, the main language of Malawi, in addition to those in chiShona. That has been discontinued. In the case, that may be reasonable; the big influx of Chew-speakers from Malawi, Mozambique and Zambia occurred during colonial rule. Those men are now old. Their wives are mostly Shona and their children, now grown up, speak Shona as their first language. If you want to find Chewa speakers in Mbare today, they are more obvious in the mosque than in any Christian church, another of their gathering places is the bar opposite the mosque, where men gather on a Sunday afternoon and play the Malawian version of a traditional African board game. Aprt from that, a number of those who have lost their families or never married now live in the care of Mother Teresa’s sisters. I try to use a little Chewa at Mass in their chapel, but the demand for it is not great. They like to say a few simple common prayers, especially “Our Father” and to sing a few well-known hymns in chi Chewa, but most of them made contact with th Catholic church here in Zimbabwe and are used to following Mass in Shona.
The other minority languages have deeper roots in Zimbabwe, but although the new constitution recognises about a dozen languages on paper, the resources are not there to publish government information in all those languages, so nobody makes the attempt. 34 years after independence, there is no complete set of text books for primary schools in any of the minor languages. If children cannot be taught in their own languages, those lnguages are under threat.
I would be ignoring the elephant in the sitting room if I did not mention the biggest tensions are between the two largest ethnic groups, the Shona and Ndebele, with each side having grounds for complaint about oppression by the other at some time in the past 150 years. That deserves to be a topic on its own.