Any existing LHx will likely need to be modified to operate the F-35B. Even the brand new USS America LHA needs modification to its deck structure, and relocation of under deck equipment to mitigate thermal loads that were not anticipated during its design (this is in addition to the new Thermion deck coating.) It is a safe bet that both the Spanish and Italian LHD designs will need similar modifications, plus their aviation fuel bunkerage, weapons storage and MX spaces will need to be enlarged / modified. The USN will manage the thermal situation by rotating landing spots until each ship visits the yard to be modified - not sure if this is possible on smaller deck LHDs.