Thanks for the reply.
I have copied the files manually and now it works fine.
But joomla was correctly configured in Spanish es-ES before installing AwoCoupon and AwoReward, however the files in Spanish were not installed. Something is wrong.
I have repeated the installation of the modules with a fresh joomla just installed v. 3.9.18 and AwoCoupon module cannot be installed.
This is the error:
0 Call to a member function get_home_link() on null
/home/carlos/www/pruebas.local/public_html/joomla/administrator/components/com_awocoupon/awocoupon/library/class-awocoupon-library-http.php:39
Call stack
# Function Location
1 () JROOT/administrator/components/com_awocoupon/awocoupon/library/class-awocoupon-library-http.php:39
2 Awocoupon_Library_Http->request() JROOT/administrator/components/com_awocoupon/helper/class-awocoupon-helper-update.php:242
3 AwoCoupon_Helper_Update->install_languages() JROOT/administrator/components/com_awocoupon/helper/class-awocoupon-helper-update.php:41
4 AwoCoupon_Helper_Update->install() JROOT/tmp/install_5ea2a9e4eed45/install.awocoupon.php:54
5 awocouponInstall->install() JROOT/tmp/install_5ea2a9e4eed45/install.awocoupon.php:27
6 com_awocouponInstallerScript->install() JROOT/libraries/src/Installer/InstallerAdapter.php:1048
7 Joomla\CMS\Installer\InstallerAdapter->triggerManifestScript() JROOT/libraries/src/Installer/InstallerAdapter.php:790
8 Joomla\CMS\Installer\InstallerAdapter->install() JROOT/libraries/src/Installer/Installer.php:521
9 Joomla\CMS\Installer\Installer->install() JROOT/administrator/components/com_installer/models/install.php:187
10 InstallerModelInstall->install() JROOT/administrator/components/com_installer/controllers/install.php:35
11 InstallerControllerInstall->install() JROOT/libraries/src/MVC/Controller/BaseController.php:710
12 Joomla\CMS\MVC\Controller\BaseController->execute() JROOT/administrator/components/com_installer/installer.php:19
13 require_once() JROOT/libraries/src/Component/ComponentHelper.php:402
14 Joomla\CMS\Component\ComponentHelper::executeComponent() JROOT/libraries/src/Component/ComponentHelper.php:377
15 Joomla\CMS\Component\ComponentHelper::renderComponent() JROOT/libraries/src/Application/AdministratorApplication.php:101
16 Joomla\CMS\Application\AdministratorApplication->dispatch() JROOT/libraries/src/Application/AdministratorApplication.php:159
17 Joomla\CMS\Application\AdministratorApplication->doExecute() JROOT/libraries/src/Application/CMSApplication.php:196
18 Joomla\CMS\Application\CMSApplication->execute() JROOT/administrator/index.php:51
System:
Joomla! 3.9.18 Stable [ Amani ] 21-April-2020 19:30 GMT
mysql 5.7.29-0ubuntu0.18.04.1
php 7.2.29-1+ubuntu18.04.1+deb.sury.org+1
Apache/2.4.29 (Ubuntu)
Regards.
