Ì did not try that way.
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please refer this note 1590030 - GRC 10.0, 10.1 Plug-in & AC 5.3 VIRSA (RTA) Co-Existence
and
Please note the following points before upgrade to the AC 10.1 Plug-Ins.
1. Our recommendation is to upgrade both front-end (GRCFND_A) and back-end plug-in (GRCPINW & GRCPIERP) components to AC 10.1 which also contains the AC 5.3 RTA.
2. During the time of transition, you can still connect to AC 10.1 Plug-in (GRCPINW & GRCPIERP) from AC 10.0 front-end.
3. And also, you can connect to AC 10.0 Plug-in (GRCPINW & GRCPIERP) from AC 10.1 front-end as long as support pack of AC 10.0 plug-in is SP10 and above. However, some new AC 10.1 functionalities such as Organization Rule Wizard, Custom User group creation and EAM DB log collection will not work.