'may prove challenging' is correct and usable in written English.
You can use it to express the possibility that a certain task or activity may be difficult or require a lot of work and effort. For example: "Designing an effective marketing plan for a brand new product may prove challenging."
But judging from the stance of one opponent, Rosemary J. Uzzo, that process may prove challenging.
But based on reactions at French Hill, gaining mass public support may prove challenging.
They are just one of the genuinely creepy elements that may prove challenging for younger children.
But attacking the Obama administration on foreign policy may prove challenging.
But with risks to come in the second half from Mexico and elsewhere, this may prove challenging.
Given his history -- this is the man who once considered producing a special called "The World's Most Embarrassing Throw-up Moments" -- that may prove challenging.
And while many admirers will be delighted, for some purists the television series to be screened next year may prove challenging.
Randy Taraborrelli's "Jackie, Ethel, and Joan" and Elisabeth Veit's "Jacqueline Kennedy"), may prove challenging for audiences accustomed to a more respectful, empathetic approach.
And although some references may prove challenging to Americans, the wealth of period detail — about tactics in battles fought with cavalry and cannon, for example, and the gruesome outcomes — is impressive.
The new editor will be part of a healthy franchise that includes the Essence Festival, the brand's annual entertainment event, but running the magazine — once seen as a lifestyle and beauty beacon for African-American women — may prove challenging.
For people with established heart disease and those known to face a high risk of developing it, the recommended consumption of about one gram a day of the omega-3 fatty acids in fish oils may prove challenging without the supplements.
