"challenging endeavor" is a correct and usable phrase in written English. It can be used to describe a difficult but rewarding task or venture. For example, "Developing a successful business plan was a challenging endeavor, but the rewards were worth the effort.".
Conducting environmental risk assessment of engineered nanomaterials has been an extremely challenging endeavor thus far.
Investing in long-term retention can be a time-consuming and challenging endeavor, and often one that is never fully complete.
However, experimental complications mean this is still a challenging endeavor.
Characterizing Makers and their pathways is a challenging endeavor.
This one will likely be their most challenging endeavor yet.
Membrane protein structure determination remains a challenging endeavor.
Together, these combine to make NIH-funded research in correctional settings a challenging endeavor.
When I feel like I can't trust my brain 100%, Ludwig really comes in handy. It makes me translate and proofread faster and my output more reliable.
Claudia Letizia
Head Translator and Proofreader @ organictranslations.eu