My Spouse is currently on L Dependent permit and recieved job offer. Employer is going to submit Permit ( B) for her in Bern
I am on primary L Permit in Basel Stadt
a. What is the process to apply for dependent B permit for me?
b. Do We need to apply for B permit together with primary applicant
or after getting the B Permit for my spouse and then apply separately for dependent B permit?
c. Is it technically possible that I can work on L and spouse can work on B permit?

Not much point in asking it twice

https://www.englishforum.ch/permits-...ml#post3295287

and I think you're confused about what is actually happening.

To employ a non-EU L permit dependent an employer has to meet certain market and labour conditions to be able to hire them. There is no change to the permit type. All that happens is the ability to work gets added to the dependent L permit since atm it only allows the dependent to live here and not work.

"Family members of a holder of a short-term residence permit (Article 26 OASA) do not enjoy the right to exercise a lucrative activity. The exercise of a lucrative activity is subject to authorization. Upon admission, a request from the employer respecting the remuneration and working conditions in use in the locality and branch must have been submitted. In addition, members of the family of a holder of a short-stay permit (Article 26 OASA) must have professional qualifications (personal qualifications, Article 23 LEtr).

The possibility of engaging in a gainful activity for family members is related, according to art. 26 and 27 OASA, for the duration of the authorization of the person who has benefited from family reunification. If the spouse's residence permit is not renewed, his family members can not claim a right to continue their gainful activity (Article 6 (2) OASA)."