It looks they're using the same system for qualification as for OG 2018.
Slovenian Hockey Federation announced that they'll host Preliminary round qualification in Jesenice (06.-09. 02. 2020.)
Article in Slovenian
I will try to create all groups using the same system as for OG 2018.
Olympic Winter Games, Men’s Ice Hockey Tournament
Group A: TBD(1), TBD (6), TBD (7), China (12)
Group B: TBD (2), TBD (5), TBD (8), TBD (11)
Group C: TBD (3), TBD (4), TBD (9), TBD (10)
Final Olympic Qualification
Group D: Slovakia (9), Belarus (14), Austria (15), Qualifier 6
Group E: Latvia (10), France (13), Italy (16), Qualifier 5
Group F: Norway (11), Denmark (12), South Korea (17), Qualifier 4
Olympic Qualification Preliminary Round 2
Group G: Slovenia (18), Japan (23), Lithuania (24), Qualifier 8
Group H: Kazakhstan (19), Poland (22), Ukraine (25), Qualifier 7
Group J: Great Britain (20), Hungary (21), Estonia (26), Romania (27) or some Qualifier.
Olympic Qualification Preliminary Round 1
This preliminary round depends on how many nations will apply to participate in qualifications. Netherlands and Croatia (maybe even Romania) will probably be the hosts of these
NOTE: This is not official. We'll probably see the official schedule in the upcoming days.