PoE - generally speaking - is a can of worms.
Each and every device (particularly Mikroitk, but not only) has its own small (or large) quirk(s).
There are two main approaches:
- active ("standard" 802.3af/at/bt), essentially negotiated 48 V
- passive
which can be divided in two:
2.1) 24 V
2.2) 48 V
both of which can use either Mode A or Mode B (the difference is on which pairs the DC power is applied)
Even if 802.3af/at/bt are a standard, many Mikrotik devices have small deviations from it, particularly regarding the max power available on a given PoE port out.
And as well other manufacturers devices may behave "differently" (from what Mikrotik expects) or their OS/setting may miss some needed settings.
It is a bit like the early Linux times, you first need to choose tentatively the hardware, then BEFORE actually buying it see if it is compatible, this is point #19 here:
GP & CSA for Mikrotik devices
Personally (but I am old, and particularly old style) I see PoE as a very good thing, but essentially a way to simplify installation and centralize the power on/power off switches of the various devices.
So - even if they do exist - I don't see any particular need (on normal SOHO setups) to have the power controlled remotely (i.e. a PoE OUT switch/network device) and using normal injectors with normal power supplies is good enough.
BTW, this latter approach allow to have - on the same network any combination of 24V and 48V active and passive (as long as you don't mix cables).