The entitlement to a representative is well-established when a complainant objects to access/disclosure of their private data and the prosecution seek a witness summons (see s.15 and s.17 of the Criminal Procedure Rules).
This is reflected in the CPS’ own guidance, which states that where records are sought via a witness summons, the complainant “will be entitled to have his/her views put before the court…by the prosecutor on the victim’s behalf or by the victim in person or in writing, or by someone acting on her/his behalf” (see also the Judicial Protocol, 2013, para.47).
There are, however, concerns that victim-survivors’ lawyers would not have rights of audience at court before or unless the CPS applied for a witness summons. There is little commentary on what is permitted before this stage, but R (TB) v Stafford Crown Court  EWHC 1645 highlighted the importance of early engagement with the complainant and/or their representative (lawyer).
Providing rights to oppose evidence does change the legal status of complainants and “need not compromise the substantive rights of the accused. It is not a zero-sum game, where additional rights for complainers can only be gained at the expense of a fair trial for the accused” (Raitt, 2010, p.54).
We are not arguing for victim-survivors to be given party status in legal proceedings.
Looking to our closest neighbours shows how independent legal advocacy can work within an adversarial system.
Victim-survivors in the Republic of Ireland are entitled to legal representation regarding applications to introduce evidence about their sexual behaviour. A recent review recommended this was extended to cover counselling records.
A review of Scots Law also provides relevant precedence that provided complainants with legal aid to make meaningful representations on access to, and disclosure of, their medical records (WF Petitioner  CSOH 27), digital downloads (AR v HM Advocate  HCJ 81), and sexual history (RR v HM Advocate 
HCA/2020/4/XM, not yet published).
The consultation documents on the introduction of legal representation for Irish complainants is particularly useful. They state that denying victim-survivors party status at trial does not preclude their representative making submissions at an application hearing away from the jury.