Can my students sit Cambridge IGCSE Co-ordinated Sciences (9-1) 0973 with Cambridge IGCSE Physics (9-1) 09702?

No, not in the same series of exams. In a single series of exams some combination of syllabuses are not allowed and you should refer to section 5 ‘What else you need to know’ in the Co-ordinated Sciences (9-1) 0973 syllabus to find out the exceptions when combining IGCSE Co-ordinated Sciences with other Cambridge International syllabuses.