Thank you M_img.
My another question is what if the spouse was a J1 visa holder in the past but already received a J-1 visa waiver (favorable recommendation) and no longer subject to HRR. Would that causes any trouble for him/her to apply for J2 visa in the future?
I guess what I'm also curious is that would the favorable recommendation on the waiver prevent anyone to reapply for the J1 in the future (with the different sponsor organization)? -- just curious since I can't seem to find any information about it anywhere. Of course, nobody wants to go through the process of applying for J visas and the waivers twice.