list of traditional Chinese sorted/grouped by number of strokes
lists which contain around 500 characters

you must be kidding  500 only?
try the 國語辭典, maintained by the ministry of education, taiwan; it’s under cc 3.0. you may download the excel file here:
https://language.moe.gov.tw/001/Upload/Files/site_content/M0001/respub/dict_reviseddict_download.html
the first excel file should suit your need, it contain 8000+ characters, with colume indicated the stroke number, and radical.
have fun :)