Malaysian national police chief Mohamad Fuzi Harun said the composite images were based on eyewitness descriptions. Israel dismissed the charge.
The sketches distributed to all police stations and border patrols nationwide showed bearded, light-skinned men of European or Middle Eastern heritage, investigators said.
It said Al Batsh had a doctorate in electrical engineering and power electronics from the University of Malaya and received his master's and bachelor's degrees in electrical engineering from the Islamic University of Gaza, an independent school in the Hamas-ruled Gaza Strip.
"We believe that the suspects are still in the country", Fuzi said, adding that they may have changed their appearance.
Malaysian police have released a new image of one of the two men suspected of shooting dead a Hamas militant in Kuala Lumpur, as they said the pair were still at large in the country.
"Right now, we believe they are still in the country and hope that anyone, who has information on these two to alert the police", he said. "We say to them, we will not let them sow our lands and enjoy them".
Malaysian Deputy Prime Minister Ahmad Zahid Hamidi said on Saturday the suspects were believed to be Europeans with links to a foreign intelligence agency.More news: Rahul failed leader, Congress impeachment to end with Karnataka results - BJP
Al-Batsh traveled locally and overseas to speak on Palestinian issues and was due to fly to Turkey for a conference when he was killed, police said.
Hamas leader Ismail Haniyeh said Mossad had been behind past attempts to kill Palestinian scientists, and the attack on Mr Batsh "follows this sequence".
Batsh's corpse is set to be flown to Egypt later in the day before being transported on to Gaza for burial.
Malaysia has no diplomatic relations with Israel.
Israel's use of live fire, killing at least 35 Palestinians, has drawn worldwide criticism.
Israel's Mossad has been accused of several high-profile killings involving Palestinians around the world, although Israel has consistently denied the accusations.
The men were taken in Tuesday morning shortly after they crossed the security fence at the border, according to the Israel Defene Forces.