Two H1B petition, one is extension approved and another is transfer.Going for stamping with extension approved.

So I have H1B extension approved with Employer A and planning to go for drop box stamping as i am drop box eligible. However I also got an offer with Employer B and that transfer petiotion is also approved now.

I will still continue to go for stamping with Employer A and once i am back in here US then i am planning to join Employer B.

Will having two petition cause any problem while stamping?

No it won’t cause any problem. Many people who have worked in US for a long time would have faced this issue.

Do not worry about it.

Good Luck!