User securables are more relevant at user level hence, you need to check them for each database one by one. Either you can find them for one specific user within a database or for all the users in that database.
I check them using below script for one specified user:
select USER_NAME(p.grantee_principal_id) AS principal_name,
dp.type_desc AS principal_type_desc,
p.class_desc,
OBJECT_NAME(p.major_id) AS object_name,
p.permission_name,
p.state_desc AS permission_state_desc
from sys.database_permissions p
inner JOIN sys.database_principals dp
on p.grantee_principal_id = dp.principal_id
where USER_NAME(p.grantee_principal_id) = 'db_user'
If you want to check for all the users in the database, just remove the last where clause as below:
select USER_NAME(p.grantee_principal_id) AS principal_name,
dp.type_desc AS principal_type_desc,
p.class_desc,
OBJECT_NAME(p.major_id) AS object_name,
p.permission_name,
p.state_desc AS permission_state_desc
from sys.database_permissions p
inner JOIN sys.database_principals dp
on p.grantee_principal_id = dp.principal_id
You need to check class_desc
column having value OBJECT_OR_COLUMN
I am not very sure however you may use the same script for server level securables being in master database however that should already be taken care by login transfer using sp_help_revlogin
For more details on securables, you may check this answer.
Hope this helps.