The Baggies could be without Alex Mowatt in Wales – with the former Leeds man struggling with a foot injury.
Molumby impressed in a 30 minute cameo from the bench in the win over Blues last Friday.
But prior to that, he had only made two brief substitute appearances since joining the Baggies on loan from Brighton.
“He’s very much ready,” Ismael said when asked if Molumby is ready to start.
“He has had the previous games. Every time we try to find ways to build him up, to make sure he has that connection with the team and that he understands our way to play.
“The six position is a very strategic position for us. Lots of work and brain work for the six, but he improves week after week.
“It started in Cardiff when he came in, then Stoke he came in and was good and now against Birmingham he had a great attitude.
“He’s ready for the next step for sure.”
While Mowatt is a doubt for tomorrow’s game, Ismael confirmed Grady Diangana won’t be involved with the forward struggling with a hamstring strain.
But the former West Ham man will be fit to face Bristol City on Saturday.
“Alex we are assessing every day,” Ismael confirmed.
“Today (Tuesday) he did a training session, so we will see.
“Day by day, that is how it is.
“Grady, it will be too soon for the Swansea, because he only started training with the team today – with the speed tests.
“We don’t need to rush or risk anything.
“For sure he’ll be back against Bristol City.”