Sandbox

SELECT 
  cscart_categories.*, 
  cscart_category_descriptions.*, 
  cscart_seo_names.name as seo_name, 
  cscart_seo_names.path as seo_path 
FROM 
  cscart_categories 
  LEFT JOIN cscart_category_descriptions ON cscart_category_descriptions.category_id = cscart_categories.category_id 
  AND cscart_category_descriptions.lang_code = 'fr' 
  LEFT JOIN cscart_seo_names ON cscart_seo_names.object_id = 868 
  AND cscart_seo_names.type = 'c' 
  AND cscart_seo_names.dispatch = '' 
  AND cscart_seo_names.lang_code = 'fr' 
  AND cscart_seo_names.company_id = cscart_categories.company_id 
WHERE 
  cscart_categories.category_id = 868 
  AND (
    cscart_categories.usergroup_ids = '' 
    OR FIND_IN_SET(
      0, cscart_categories.usergroup_ids
    ) 
    OR FIND_IN_SET(
      1, cscart_categories.usergroup_ids
    )
  ) 
  AND cscart_categories.company_id = 3

Query time 0.00046

Explain
id	select_type	table	type	possible_keys	key	key_len	ref	rows
1	SIMPLE	cscart_categories	const	PRIMARY,c_status,p_category_id,idx_category_id	PRIMARY	3	const	1
1	SIMPLE	cscart_category_descriptions	const	PRIMARY	PRIMARY	9	const,const	1
1	SIMPLE	cscart_seo_names	const	PRIMARY,dispatch	PRIMARY	210	const,const,const,const,const	1

Result

category_id	parent_id	id_path	level	company_id	usergroup_ids	status	product_count	position	timestamp	size_chart_id	is_op	localization	age_verification	age_limit	parent_age_verification	parent_age_limit	selected_views	default_view	product_details_view	product_columns	is_trash	staff_notes	action	lang_code	category	description	meta_keywords	meta_description	page_title	age_warning_message	custom_header	seo_name	seo_path
868	744	744/868	2	3	0	A	1	20	1485298800	0	N		N	0	N	0	a:3:{s:21:"products_multicolumns";s:21:"products_multicolumns";s:24:"products_without_options";s:24:"products_without_options";s:10:"short_list";s:10:"short_list";}	products_multicolumns	default	0	N			fr	Panneau Mural 3D		Panneau en gypse ; Panneau en bois ;	Panneau en gypse ; Panneau en bois ; résistants au feu ; non-toxiques ; 100% ECO ; nettoyage facile ; montage facile ; cachent parfaitement les surfaces inégales et les imperfections ; possibilité d'installer verticalement et horizontalement ;	Panneau Mural 3D			panneau-mural-3d	744