Hi! In regards to Groups and if an inactive Leader's rank can be transferred. It actually can, however, requirements must be met for the impeachment process and it does cost ingots to impeach. You can find great resources on the forum, for example, here is a resource about groups including the impeachment process.

Here is an excerpt from the above linked resource (Courtesy of the information goes to Narutlih):

Q: Can inactive leader's rank be transfered?

A: After 1 week of leader's inactivity he can be impeached with ingots. Seniors can impeach in the first 24 hours after 7 days expire. After 48 hours - anbu, after 72 - elite, and then, finally, normal members. It costs 120 ingots to impeach.

TLDR: This means that it is possible for any members of the group to impeach after the specified duration of inactivity. However, it is only possible as long as there is an active member of the group available to impeach. If there are no members of the group currently active to impeach, it is not possible for a player outside of the group to take the Leadership rank of a Group they are not part of.