Markovic was signed from Benfica for around £20 million earlier this summer, while Spanish left-back Moreno was brought in from Sevilla for a reported £12 million.
Both players made their debut in Monday evening's 3-0 reverse against Manchester City at the Etihad, with Markovic coming off the bench to add some much-needed impetus to Liverpool's attack.
Moreno was culpable for Stevan Jovetic's first goal, but looks as though he will add some dynamism down the left side for Brendan Rodgers' side this season and Henderson has been impressed by both players already.
The Reds travel to Tottenham Hotspur this Sunday with both players expected to be in the squad, and Henderson has talked up the duo after their respective performances at the Etihad.
He told the club's official website: "Alberto Moreno got plenty of crosses in and Lazar Markovic came on later in the game and looked very sharp and confident.
"I thought they were brilliant and we've still got Mario Balotelli to come into the side too, so hopefully he can play some part at the weekend.
"I think you only have to look at the players who made their debut against City, the way they worked getting up and down the pitch. If you look at the game against City, we dominated it for the first 40 minutes with the ball and were arguably the better side. Then they got one just before half-time and it gave them a big lift at an important point in the game."
Markovic and Moreno are just two of nine signings made by Rodgers ahead of the new season, and the Reds have spent close to £120 million this summer - the biggest outlay in their history.
Moreno and Markovic have been joined by Adam Lallana, Rickie Lambert, Emre Can, Mario Balotelli, Dejan Lovren and Javi Manquillo, while Divock Origi will join the club next summer after he was loaned back to Lille following his £10 million switch.
Meanwhile Liverpool will be fairly confident of progression to the knockout stages of the Champions League after they were drawn against Real Madrid, Ludogorets and FC Basel in Group B on Thursday.
The Reds return to the competition they won back in 2005 next month when they take on Bulgarian side Ludogorets on September 16, before meeting the Swiss outfit on October 1.
However, all eyes will be on the two meetings against Los Blancos and the Reds travel to Madrid to play the current holders on November 4 after hosting them at Anfield on October 22.