I just wanted to post this here for anyone trying to figure out how to change a context key. Thanks to @theuros for sharing this list with me!
1. `*UPDATE* modx_context **SET** `key` = 'web-en' **WHERE** `key` = 'web2';` 2. `*UPDATE* modx_access_context **SET** `target` = 'web-en' **WHERE** `target` = 'web2';` 3. `*UPDATE* modx_access_media_source **SET** `target` = 'web-en' **WHERE** `target` = 'web2';` 4. `*UPDATE* modx_access_category **SET** `context*_*key` = 'web-en' **WHERE** `context*_*key` = 'web2';` 5. `*UPDATE* modx_access_elements **SET** `context*_*key` = 'web-en' **WHERE** `context*_*key` = 'web2';` 6. `*UPDATE* modx_access_resources **SET** `context*_*key` = 'web-en' **WHERE** `context*_*key` = 'web2';` 7. `*UPDATE* modx_access_resource_groups **SET** `context*_*key` = 'web-en' **WHERE** `context*_*key` = 'web2';` 8. `*UPDATE* modx_access_templatevars **SET** `context*_*key` = 'web-en' **WHERE** `context*_*key` = 'web2';` 9. `*UPDATE* modx_context_setting **SET** `context*_*key` = 'web-en' **WHERE** `context*_*key` = 'web2';` 10. `*UPDATE* modx_media_sources_contexts **SET** `context*_*key` = 'web-en' **WHERE** `context*_*key` = 'web2';` 11. `*UPDATE* modx_media_sources_elements **SET** `context*_*key` = 'web-en' **WHERE** `context*_*key` = 'web2';` 12. `*UPDATE* modx_context_resource **SET** `context*_*key` = 'web-en' **WHERE** `context*_*key` = 'web2';` 13. `*UPDATE* modx_site_content **SET** `context*_*key` = 'web-en' **WHERE** `context*_*key` = 'web2';`