Cannot create Federated View
You are using FederatedX engine and since you are not specifying column definitions explicitly, it is trying to perform assisted discovery to retrieve the structure of the table. It cannot do it with the underlying "table" being a view, so you are getting the error. 

Instead, try to specify the columns:

-- remote
CREATE VIEW `DB_1`.`testView` AS SELECT "test_line"

-- local
CREATE TABLE `DB_1`.`testView` (test_line varchar(16))
ENGINE=FEDERATED CONNECTION='remote_server';