I do not think the Mbed community is “so huge”, to be honest it is very weak.
I usually saw projects with a resistive touch screen - Lib for ILI9341 8bit - Mbed OS - Arm Mbed OS support forum
About the library. I do not think it is about Mbed environment. When I look into STM32CubeF0/Middlewares/ST/STM32_TouchSensing_Library/inc at master · STMicroelectronics/STM32CubeF0 (github.com) I see the library does not have any preparation for STM32F0xx. So how you can see there are files for STM32L1xx. And also a tsl_conf.h must be prepared before usage.
BR, Jan