The match is taking place to honour Chris Brunt and James Morrison, for their service to the club across a combined 25 seasons.
Tickets for the clash went on sale earlier this year - and now the first three players to line up in the game have been announced.
Olsson, a club legend at The Hawthorns, will play for one of the sides, alongside both Bednar and Jones.
The big Swede arrived at the club in 2008 and played over 260 times before departing in 2017.
Bednar, who retired in 2016, scored 34 times for the club in 104 games - while Jones spent three seasons with the club before he went on to join Sunderland.
Both Brunt and Morrison, who remain part of the coaching staff at the club, have selected the Albion Foundation as their partner for the game - with the profits going to the foundation and towards the work they do in the community.
Tickets for the game are £15 for over 17s and £5 for under 16s.
Season ticket holders from either the 2021/22 campaign or the 2022/23 campaign can take advantage of discounted prices up until Friday, July 1 - and hospitality packages are also available from £45 per person.