LegisPalop is a site that brings together legislation passed by Portuguese-speaking countries in Africa. The countries covered are Angola, Cape Verde, Guinea-Bissau, Mozambique and São Tomé and Príncipe. Obviously, the texts are in Portuguese, but there is always Google Translate, or the equivalent, if you don’t speak the language.
Anyway, from now until 15 August the site is offering free 48-hour access. So, you can access all of the constitutional laws, and other legislation, for these countries for a certain period.
Some of the constitutional texts for these countries are easy to find. However, others are very difficult. For example, I have finally been able to find the text of the February 1993 constitutional amendment in Guinea-Bissau that introduced semi-presidentialism and confirmed that the amendments in May and December 1991 did not! Another text that is really difficult to find is the October 1990 constitutional law of Cape Verde that introduced semi-presidentialism. The 1992 amendment is easy to find, but the original 1990 law is buried away in such websites.
So, this is a great resource and for a limited period it is free.