Dear @Kazuya.Nishiyama,
Regarding the difference between NBlInpSt and BldNodes in ElastoDyn, see my post dated Jul 2, 2024 in the following forum topic: Blade crack modeling in NREL 5-MW baseline wind turbine, modifying EdgeStff.
Regarding the blade gauge node outputs, the output name should be Spn4MLxb1 for the reaction loads at output node 4 of blade 1 (you have the “1” and “4” swapped).
Best regards,