After doing speed test, my external HDD is 40% faster in data transferring speed after formatted it to APFS from HFS+ or even ExFat. But I hear people saying on the internet that mechanical disk should be formatted with HFS+ and APFS is slower for it and destroy the hard drive over times. I’m very insured about using APFS right now even it showed to me that it’s the fastest.
About my computer: Macbook pro 2012, Intel Chip, OS Catalina, SSD SATA internal drive About my external drive: Seagate GoFlex desk HDD 3TB