I've a SucceX-Force 5.8g, if I press the "Output Level Button", the green light will flash accordingly as the manual says (1, 2, 3 or 4 times).

But I see no better signal, and the OSD on googles keep showing me the same power (25mw).

Also, if I unplug the battery and plug again, the output power returns to the saved one (25mw).

The same goes with band and frequency. What i'm doing wrong?

You may have to “unlock” that vtx before u can make power changes.. or it could be in “pit mode”.

I hate button menus on vtx’s and simply prefer VTX SmartAudio control.

Did you try setting it up via FC using VTX SmartAudio control?

One other thing I missed mentioning is if you have the correct vtx tables loaded in Betaflight as by default if there is no vtx table setup or the table is incorrect then the vtx reverts to the lowest possible power level which is 25mW in most cases.

I thought the new version of BF had "presets" for VTXs now? true.. Tramp or SA?
SA is nice, but sometimes u need the uart and buttons are needed to "unlock" a vtx

Yes, 4.3 has presets for vtx’s but unless you are using RushFPV or IRC or TBS vtx’s not all vtx’s are available including none of the iFlight vtx’s.

We need a button but even the IRC Tramp HV transmitter had a disclaimer I remember in the manual:
“First, a disclaimer, this transmitter was not designed to use the button as the primary user-interface.”

Some of the newer vtx’s have a more intuitive button menu along with led responses but it’s still frustrating to remember the button and led sequence. Just use the button as a last resort but its not user friendly in most cases which is why SA function is a must have.