Under EASA if you have an Aeros rating plus either an FI or CRI rating you will be able to instruct for it.
It's not quite as simple as that. In order to instruct for the Aerobatic Rating, an instructor must have been assessed as competent in this activity by a FIC Instructor. The reference is in EASA Part FCL:
FCL.905.FI FI — Privileges and conditions
The privileges of an FI are to conduct flight instruction for the issue, revalidation or renewal of:
(f) a towing or aerobatic rating, provided that such privileges are held and the FI has demonstrated the ability to instruct for that rating to an FI qualified in accordance with (i) below;
An "FI qualified in accordance with (i) below" referred to above is the equivalent of an FIC Instructor (in the UK).