It is not necessary that handover is mandatory if two eNodeB's are connected via X2 link. Procedures over the X2 link are categorized into two groups:
1. Mobility Procedures
2. Global Procedures
One eNodeb may support only global procedure , not necessary to support handover as well.
If you go through 3GPP TS 36.423 then these procedures are clearly defined.
Please feel free to ask any further query if you have or expecting more clarity.