In my opinion Huawei can take legal action against Trump imposed bans in EU courts and EU competition commission. In US courts I do not see much hope as those bans are imposed under presidential emergency laws. But EU competition commission would love to take cases against Google for restrictive business practices. They are already taking measures against Google for tying play store access and its forces apps with android license. In my opinion it should be individual users choice which app store to use and which apps to use to access a service offered by a company. A service provider should neither restrict nor force user to use specific market place or apps to consumes its services.