Let's just create a role that populates the Linode inventory..

roles/inventory/linode_inventory/tasks/main.yml

@@ -0,0 +1,17 @@
+---
+- name: Run Linode dynamic inventory script
+  ansible.builtin.command: "{{ playbook_dir }}/roles/inventory/linode_inventory/files/linode_inventory.py"
+  register: linode_inventory_raw
+  changed_when: false
+
+- name: Parse JSON inventory output
+  ansible.builtin.set_fact:
+    linode_inventory: "{{ linode_inventory_raw.stdout | from_json }}"
+
+- name: Add Linode hosts dynamically
+  ansible.builtin.add_host:
+    name: "{{ item.key }}"
+    ansible_host: "{{ item.value.ansible_host }}"
+    groups: all
+  loop: "{{ linode_inventory['_meta']['hostvars'] | dict2items }}"
+