mb_strlen() expects parameter 1 to be string, array given [conf.import.php:130 ? CConfigurationImport->import() ? CConfigurationImport->processDiscoveryRules() ? CAPIObject->create() ? CAPIObject->__call() ? czbxrpc::call() ? czbxrpc::callAPI() ? call_user_func() ? CDiscoveryRule->create() ? CDiscoveryRule->createReal() ? DB::insert() ? DB::checkValueTypes() ? zbx_strlen() ? mb_strlen() in C:\xampp\htdocs\2.2\frontends\php\include\func.inc.php:955]
Array to string conversion [conf.import.php:130 ? CConfigurationImport->import() ? CConfigurationImport->processDiscoveryRules() ? CAPIObject->create() ? CAPIObject->__call() ? czbxrpc::call() ? czbxrpc::callAPI() ? call_user_func() ? CDiscoveryRule->create() ? CDiscoveryRule->createReal() ? DB::insert() ? implode() in C:\xampp\htdocs\2.2\frontends\php\include\classes\db\DB.php:450]
Error in query [INSERT INTO items (name,type,snmp_community,snmp_oid,delay,status,snmpv3_contextname,snmpv3_securityname,snmpv3_securitylevel,snmpv3_authprotocol,snmpv3_authpassphrase,snmpv3_privprotocol,snmpv3_privpassphrase,delay_flex,params,ipmi_sensor,authtype,username,password,publickey,privatekey,port,filter,lifetime,description,key_,trapper_hosts,hostid,interfaceid,flags,value_type,data_type,itemid) VALUES ('erest1','0','','','30','0','','','0','0','','0','','','','','0','','','','','',Array,'30','','erest1','','10105','2','1','4','0','23680')] [Unknown column 'Array' in 'field list']
SQL statement execution has failed "INSERT INTO items (name,type,snmp_community,snmp_oid,delay,status,snmpv3_contextname,snmpv3_securityname,snmpv3_securitylevel,snmpv3_authprotocol,snmpv3_authpassphrase,snmpv3_privprotocol,snmpv3_privpassphrase,delay_flex,params,ipmi_sensor,authtype,username,password,publickey,privatekey,port,filter,lifetime,description,key_,trapper_hosts,hostid,interfaceid,flags,value_type,data_type,itemid) VALUES ('erest1','0','','','30','0','','','0','0','','0','','','','','0','','','','','',Array,'30','','erest1','','10105','2','1','4','0','23680')".

Export host from 2.3
Import to 2.2

Missed input validation