'essential for them' is correct and usable in written English.
You can use it to indicate that something is necessary for a certain group of people. For example, "Providing access to educational materials is essential for them to reach their full potential."
Dhawq, direct "tasting" of experience, was essential for them.
The preservation of Mali's tradition of secularism is essential for them all.
That was because it's essential for them to control Congress -- they need maximum leeway to wreck the U.S. economy.
That's the thing about great co-op games - a well-balanced, well-designed singleplayer game is essential for them to succeed.
APP senior leadership clearly understands that a long term commitment to more sustainable practices is essential for them to succeed as a business.
Their personal experience, dual-language skills, and bicultural background are essential for them to deliver results at their work as border guardians.
Weaning citizens elsewhere off a substantial dependence on social security-style state programs, which many authorities see as essential for keeping them solvent, is likely to remain problematic.
Make sure learning has taken place: Although you shouldn't have to quiz students on what they're doing daily, making sure they have a good foundation is essential for keeping them in the loop and moving forward.
The Army was not convinced that fixed bunkers could resist repeated air attacks and was particularly concerned about the vulnerability of the launch sites' road and rail links, which were essential for resupplying them with missiles and fuel.
However, knowledge of the pathogen targets of these R genes is essential for classifying them into functional and spectral categories, evaluating the likelihood of resistance durability, and devising scientifically sound stacking strategies.
Its ability of binding to integrins is essential for activating them [ 27].
