My hibiscus has leaves that are kind of wrinkled looking and the last couple of years it has not bloomed. I keep it in house because every time I put it outside the leaves begin to lose all color and get white, like they are burnt. The wrinkled leaves I believe just started not too long ago.
Caring for Hibiscus
Certified GKH Gardening Expert
It sounds like it may need some fertilizer. When you moved it outside, it was indeed getting burnt. This article will explain how to keep that from happening: https://www.gardeningknowhow.com/houseplants/hpgen/move-houseplant-outside.htm