Hi, I can confirm that there is a conflict with BuddyPress version 12 and later. They rewrote several functions, below is a copy of the error generated when accessing the general membership page:
PHP Fatal error: ?Uncaught Error: Call to undefined function bp_core_get_user_domain() in /home/XXX/wp-content/plugins/user-switching/user-switching.php:761 Stack trace:
#0 /home/XXXX/wp-includes/class-wp-hook.php(324): user_switching->action_bp_button('')
#1 /home/XXXX/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters('', Array)
#2 /home/XXXX/wp-includes/plugin.php(517): WP_Hook->do_action(Array)
#3 /home/XXXX/wp-content/plugins/buddypress/bp-templates/bp-nouveau/includes/members/template-tags.php(198): do_action('bp_directory_me...')
#4 /home/XXXX/wp-content/plugins/buddypress/bp-templates/bp-nouveau/buddypress/members/members-loop.php(53): bp_nouveau_members_loop_buttons(Array)
#5 /home/XXXX/wp-includes/template.php(790): require_once('/home/icllms/pu...')
#6 /home/XXXX/wp-content/plugins/buddypress/bp-templates/bp-nouveau/includes/ajax.php(150): load_template('/home/icllms/pu...')
#7 /home/XXXX/wp-includes/class-wp-hook.php(324): bp_nouveau_ajax_object_template_loader('')
#8 /home/XXXX/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters('', Array)
#9 /home/XXXX/wp-includes/plugin.php(517): WP_Hook->do_action(Array)
#10 /home/XXXX/wp-admin/admin-ajax.php(188): do_action('wp_ajax_members...')
#11 {main} ? thrown in /home/XXXX/wp-content/plugins/user-switching/user-switching.php on line 761