Depends on the compensation
As you may know, while you are under H-1B status, you are not allowed to be employed for anybody other than the petitioning employer. You may have more than one H-1B petitions approved for more than one jobs, but without approval, you cannot work.
The answer to your question depends mainly on the compensation. If you are paid mainly as a compensation for your costs - travel, food, minimal preparation costs, etc. - then in all likelihood you are not engaged in employment. On the other hand, if you are being compensated for your efforts, then it starts to look a little bit like an employment or consulting arrangement, whereby you may be violating your status.
Good luck-
