In most cases the people you will be sending documents to will be using Windows, of whatever vintage, with MsOffice and particularly MsWord for Windows.
May I point out, that only you know who you are sending material to and only you will be able to ask them what they are using, and therefore should.
MsWord for Windows is an excellent multi-lingual word processor and the later versions have DTP abilities shoe horned into them. Your recipients may through reasons of cost and their poor relations with the USA, have only comparatively older hardware and software.
Many may be persisting with older and varyingly incompatible text encoding methods, not the Unicode that modern software is using. MsWord allows you to save in whatever works for them.
Pages is a bad choice for anything RtoL and Mellel is an Israeli product and very unlikely to be used by the more ardently Islamic countries and customers. Macs have virtually no support or outlet in the Middle East except for the UAE, Kuwait and Lebanon.
Peter