Complex sentence: It was later recorded by Hatshepsut that Thutmose willed the kingship to both Thutmose II and Hatshepsut, however, this was almost certainly propaganda by Hatshepsut's agents to legitimise her claim to the throne when she assumed power.
Split into simpler sentences: It was later recorded by Hatshepsut that Thutmose willed the kingship to both Thutmose II and Hatshepsut. However, this is considered to be propaganda by Hatshepsut's supporters to legitimise her claim to the throne when she later assumed power.