Formal:
* Les deux autres (literally "the two others") - This is the most common and general translation.
* Les deux restants (literally "the two remaining") - This implies that there are more than two, and you are referring to the remaining two.
Informal:
* Les deux autres (as above)
* Les deux derniers (literally "the two last") - This implies that the "other two" are the last ones in a sequence.
* Les deux restants (as above)
Example sentences:
* J'ai trois frères et sœurs, les deux autres sont plus jeunes que moi. (I have three siblings, the other two are younger than me.)
* Il y avait cinq personnes dans la pièce, les deux derniers sont partis. (There were five people in the room, the last two left.)
The choice of phrase depends on the specific situation and what you want to convey.