I've been trying to get it in fighting type raid dens, but no luck. If you know how, please tell me.
If this Pokemon learn Close Combat by earlier lvl you can go to move reminder, and if higher you can try in Max Raid battles to earn Exp. Candies and chance to drop TR 53 (list under)
You can also check daily all Watt Traders.
Max Raid Battles with chance to drop Close Combat in both games:
South Lake Miloch,
Max Raid Battles witch chance to drop TR 53 Exclusive for Sword:
North Lake Miloch
On Bubapedia is list of dens and drops on all this locations:
Dusty Bowl: https://bulbapedia.bulbagarden.net/wiki/Dusty_Bowl/Dens
North Lake Miloch: https://bulbapedia.bulbagarden.net/wiki/North_Lake_Miloch/Dens
Rolling Fields: https://bulbapedia.bulbagarden.net/wiki/Rolling_Fields/Dens
South Lake Miloth: https://bulbapedia.bulbagarden.net/wiki/South_Lake_Miloch/Dens
Stony Wildness: https://bulbapedia.bulbagarden.net/wiki/Stony_Wilderness/Dens