As @Tᴚoɯɐuo has noted, possibility and hypothesis are not synonymous.
A hypothesis does indeed connote a possibility, but that's not to say the two concepts are the same.
What's more, if you're learning English, I'm guessing you are referring to hypotheses as the antecedents of conditional sentences.
Take Lambie's minimal examples: "If you go..." / "If you went..."
Those two are hypotheses.
First one signifies a "hypothetical (but entirely possible) future event".
Second one signifies a hypothetical condition that is "presented as unlikely".
(For some reason, you believe that the person you are addressing will most probably not go.)
Hypotheses of the first kind are often (but not always) followed by consequents containing the modal verb will.
Consult Wikipedia's article on conditional sentences for further information.
Likewise, hypotheses of the second kind are often followed by consequents containing the modal verb would.
Having said all this, you must take note of the fact that both will and would are frequently encountered outside conditional sentences, which is the case in the example you have provided:
The World Bank report addresses a particular worry of Russian
authorities: that unemployment will translate into civil unrest.
There is no hypothesis here. Merely a prediction. Unemployment is a fact. And Russian authorities are simply predicting what consequences it will have.
Unemployment is going to translate into civil unrest.
(This is still a prediction, made, however, with much more certainty: We are doomed...)
If unemployment exceeded 40%, it would translate into civil unrest.
(This is a prediction of what will happen if a certain condition is fullfilled. That condition, however, seems unlikely to be fullfilled.)