I have recently repotted a hibiscus tree and now I'm seeing many yellowing leaves. The leaves that are still green are not as vibrant green as a similar hibiscus tree that was repotted at the same time.
Certified GKH Gardening Expert
Probably the stress related to the repotting is causing this. It is nothing to worry about right now but just in case, here are some other reasons the leaves may be turning yellow: https://www.gardeningknowhow.com/ornamental/flowers/hibiscus/answers-to-what-causes-hibiscus-leaves-turning-yellow.htm