This is one of the obscure records which cannot be found through Statsguru. It is however listed in the statistics section of Cricinfo. This is how it stands on the evening of Feb 7, the 4th day of the Zim-WI Test at Bulawayo:
Now KC Brathwaite and T Chanderpaul have batted on all 4 days so far, and will resume batting on the 5th morning. So they will also be added to this list. This will be the first occasion when two batsmen have batted together on all 5 days of a test.
India is well represented here by Jaisimha, Shastri and Pujara.
Other notes: Gary Ballance scored a century on debut for Zimbabwe. He had earlier scored 4 centuries for England. He joins Kepler Wessels in scoring centuries for two countries.
for a full list of those who played Tests for two countries.
Update: Brathwaite and Chanderpaul were duly added to the list above: