> MorphOS doesn`t have it done in software, so if you plan to use SSD with
> MorphOS machine it should have hardware TRIM

TRIM needs to be supported by both the hardware (firmware) and the software (operating system), so you can't use TRIM with MorphOS even when the hardware supports it. Pure "hardware TRIM" does not exist (and cannot exist by concept).

> Don`t use converters :-) There are SATA SSD drives

...for which you'd need a converter to use it with a PATA-only machine, wouldn't you? But as said, this is moot for MorphOS anyway, as it doesn't support TRIM no matter if with SATA SSD going through converter or with PATA SSD used directly.