Import Workitems with mention link in discussion to another RTC server using CSV import function

We would like to import Workitems with mention link in discussion to another RTC server using CSV import function, but it doesn't work as we imagine.

For example, we would like to import the following Workitems from Server A to Server B.

 Server A
  There are two Workitems. The Workitem numbers are 90 and 100.
  Workitem 100 has mention link in discussion field to Workitem 90.

However, the result to import is as belows:

 Server B
  There are two Workitems. The Workitem numbers are 1 and 2 which are automatically assinged from Server B.
  Workitem 1 on Server B is originally Workitem 90 on Server A.
  Workitem 2 on Server B is originally Workitem 100 on Server A.
  Workitem 2 on Server B has still mention link in discussion field to Workitem 90 on Server B. <- This is an issue.

We hope to change the mention link from Workitem 90 to Workitem 1 because Workitem 90 doesn't exist on Server B and Workitem 1 on Server B is originally Workitem 90 on Server A, but we can't adjust workitem number in discussion when importing because we can't know what number will be assigned.

I think it is root cause that we can't assign specific workitem number when importing workitems, and we can't change the discussion filed after import.

Any workarounds?

Thanks.