Needed suggestions for changing F1 to H4

My current status is on H1 with I-140 approved and at this moment I am planning to marry my fiance who stays in USA.

She completed her 1st masters and she used her OPT and STEM OPT period. Now her current status is F1 with second masters with CPT continuing with her 3rd semester.

  1. Is this a safe option to travel to India for marriage as a F1 student and convert as H4?
  2. Are there any similar cases where H4 visa get rejected while she is on F1 .?
  3. If we plan to register our marriage in USA: Can her status change from F1 to h4 in USA without any issues.?
  4. Once H4 is approved in USA will there be any issues when she go for stamping in India?

Is there any one with the similar situation and what is the best option in this conditions?