Simultaneous from different country?

[Mengineer]

Can applicant and dependents apply from different countries at same time ?

I will be applying for Global talent visa, the system allows "moving UK together" and also reference no of main applicant. But for dependent applications, its asking for VISA expiry date of main applicant just before paying IHS fee. something like contradiction ? or main applicant will get visa expiry date upon application submission which could be used in dependents application.