смена локали

есть ли способ сменить локаль в дистрибутиве без правки конфигов руками?

Псомотрите перенастройку живой системы при помощи cl-install
Также посмотрите man cl-install, обратите внимание на опцию --lang

cl-install --startup -l ru_RU
 # cl-install --startup -l ru_RU
calculate-install 2.2.19

Использование: cl-install [опции]
cl-install: ошибка: нет такой опции: --startup
Используйте `cl-install --help' для дополнительной информации
 # cl-install --live -l ru_RU
 * Пакет установлен
 * calculate-install используется для конфигурации пакетов ...                                                                                                                                 [ ok ]
 * Настройка системы ...                                                                                                                                                                       [ !! ]
 * Traceback (most recent call last):
 *   File "/usr/lib/calculate-2.2/calculate-install/pym/cl_install.py", line 2028, in configureSystem
 *     self.printByResult(self.applyTemplatesLive())
 *   File "/usr/lib/calculate-2.2/calculate-install/pym/cl_install.py", line 1070, in applyTemplatesLive
 *     dirsFiles = self.clTempl.applyTemplates()
 *   File "/usr/lib/calculate-2.2/calculate-lib/pym/cl_template.py", line 3957, in applyTemplates
 *   File "/usr/lib/calculate-2.2/calculate-lib/pym/cl_template.py", line 4039, in scanningTemplates
 *   File "/usr/lib/calculate-2.2/calculate-lib/pym/cl_template.py", line 4039, in scanningTemplates
 *   File "/usr/lib/calculate-2.2/calculate-lib/pym/cl_template.py", line 4039, in scanningTemplates
 *   File "/usr/lib/calculate-2.2/calculate-lib/pym/cl_template.py", line 4016, in scanningTemplates
 *   File "/usr/lib/calculate-2.2/calculate-lib/pym/cl_template.py", line 4065, in processingFile
 *   File "/usr/lib/calculate-2.2/calculate-lib/pym/cl_template.py", line 4812, in joinTemplate
 *   File "/usr/lib/calculate-2.2/calculate-lib/pym/cl_template.py", line 3654, in applyVarsTemplate
 *   File "/usr/lib/calculate-2.2/calculate-lib/pym/cl_datavars.py", line 253, in Get
 *   File "/usr/lib/calculate-2.2/calculate-lib/pym/cl_datavars.py", line 238, in __Get
 *   File "/usr/lib/calculate-2.2/calculate-lib/pym/cl_datavars.py", line 93, in Get
 *   File "/usr/lib/calculate-2.2/calculate-install/pym/cl_fill_install.py", line 969, in get_os_install_x11_video_drv
 *     return self.Get('os_x11_video_drv')
 *   File "/usr/lib/calculate-2.2/calculate-lib/pym/cl_datavars.py", line 253, in Get
 *   File "/usr/lib/calculate-2.2/calculate-lib/pym/cl_datavars.py", line 238, in __Get
 *   File "/usr/lib/calculate-2.2/calculate-lib/pym/cl_datavars.py", line 93, in Get
 *   File "/usr/lib/calculate-2.2/calculate-lib/pym/cl_fill.py", line 408, in get_os_x11_video_drv
 *   File "/usr/lib/calculate-2.2/calculate-lib/pym/cl_fill.py", line 404, in <lambda>
 * AttributeError: 'builtin_function_or_method' object has no attribute 'group'
 * Не удалось настроить систему

Обновите предварительно систему.

eix-sync
emerge -DNuavt @world
emerge -avt @preserved-rebuild