diff --git a/frontend/src/i18n/locales/en.ts b/frontend/src/i18n/locales/en.ts
index cdd9ad19..b2eac925 100644
--- a/frontend/src/i18n/locales/en.ts
+++ b/frontend/src/i18n/locales/en.ts
@@ -1505,7 +1505,8 @@ export default {
         partialSuccess: 'Partially updated: {success} succeeded, {failed} failed',
         failed: 'Bulk update failed',
         noSelection: 'Please select accounts to edit',
-        noFieldsSelected: 'Select at least one field to update'
+        noFieldsSelected: 'Select at least one field to update',
+        mixedPlatformWarning: 'Selected accounts span multiple platforms ({platforms}). Model mapping presets shown are combined — ensure mappings are appropriate for each platform.'
       },
       bulkDeleteTitle: 'Bulk Delete Accounts',
       bulkDeleteConfirm: 'Delete the selected {count} account(s)? This action cannot be undone.',
diff --git a/frontend/src/i18n/locales/zh.ts b/frontend/src/i18n/locales/zh.ts
index 8ef50267..8366f9c4 100644
--- a/frontend/src/i18n/locales/zh.ts
+++ b/frontend/src/i18n/locales/zh.ts
@@ -1652,7 +1652,8 @@ export default {
         partialSuccess: '部分更新成功：成功 {success} 个，失败 {failed} 个',
         failed: '批量更新失败',
         noSelection: '请选择要编辑的账号',
-        noFieldsSelected: '请至少选择一个要更新的字段'
+        noFieldsSelected: '请至少选择一个要更新的字段',
+        mixedPlatformWarning: '所选账号跨越多个平台（{platforms}）。显示的模型映射预设为合并结果——请确保映射对每个平台都适用。'
       },
       bulkDeleteTitle: '批量删除账号',
       bulkDeleteConfirm: '确定要删除选中的 {count} 个账号吗？此操作无法撤销。',