There is a substantial amount of paired watershed studies conducted by the US Forest Service, beginning with work at Wagon Wheel Gap in Colorado. The Forest Service developed additional experimental hydrologic stations in several of the major climate and physiographic areas in the US. Some Universities and also other agencies used this approach. I cited quite a few articles relative to paired catchment or watershed research in my thesis entered into researchgate. One paper I remember well was a compilation by Hibbart in about 1960 that compiled and summarized much of the water yield experiments in various vegetation types internationally. I believe the earliest paired hydrologic watershed experiments were begun in Germany, as was also early forest management. The study in Colorado involved the benefits perceived from clearcutting forest on improved water yield. The results suggested that the sedimentation from this activity in the early 1900s (ie, no BMPs back then) was so severe that there would be no benefits from the improved water yield. From memory, Raphael Zon was the principle investigator. The USFS still maintains several experimental hydrologic stations that use paired watersheds or catchments, for not only studies in water yield, but nutrient cycling, effects of varying types and degrees of management including various forest types, grasslands, climates and topography. Many researchers have been involved with numerous publications emulated from experimental watersheds. Experimental watersheds, were sometimes called or referred to as paired or barometer watersheds or catchments if conducting internet searches. Some may have even used the term basin in describing their work. The body of work is quite substantial, so you may want to attempt to select one or more experimental hydrologic study areas with similarities in climate, rainfall, vegetation, topography, etc.

There are wide range of studies on forest and grassland vegetation functional types using paired watershed approach in the US.

Just to cite few:

Zou, C. B., Turton, D. J., Will, R. E., Engle, D. M., & Fuhlendorf, S. D. (2014). Alteration of hydrological processes and streamflow with juniper (Juniperus virginiana) encroachment in a mesic grassland catchment. Hydrological Processes, 28(26), 6173-6182.

Qiao, L., Zou, C. B., Will, R. E., & Stebler, E. (2015). Calibration of SWAT model for woody plant encroachment using paired experimental watershed data. Journal of Hydrology, 523, 231-239.

Yes, here is a paper that reviews many paired watershed studies.

Global analysis of streamflow response to forest management, 2019, Evaristo and McDonnell, Nature

thanks for your advises