Who do you have at SS? Who else do you have at 2B and 1B? If Segura is an upgrade, then it might be worth it. Walker is good but nothign spectacular, and same for Morales. Segura profiles to be pretty good all around, contributing in most categories while not hurting you in any.
Depending on how many teams are in your league, its a bad trade for you. Walker and Morales are much more proven than Segura who could be years away from developing into a legit big leaguer or never at all