At 50 watts into 50 ohms, you have 50V at 1 amp.
(That makes the math easy.)
So any practical switch rated for 120 VAC at 2 amps
or higher should carry 100 watts.
Ratings for receive use are insignificant - signals
are way too small to matter.
HOWEVER, the issue often is impedance discontinuities
in the switch. As you go higher in frequency, these will
cause a higher SWR. Most switches will work on the
lower HF bands, and often on 10m, depending on
how much SWR you can tolerate due to inserting
the switch.
If you are using a tuner between the switch and the
radio, that should account for any SWR (but you may
need higher voltage and current ratings for the switch).
I’ve used standard DPDT toggle switches for switching
antennas at 100 watts, and others have used standard
household light switches (not the mercury type) mounted
in a, electrical box. Attenuators often use slide switches
due to the short internal lead lengths, even at VHF.
(They give the best results with shields across each
switch, and sometimes between them.)
One of my receivers uses a doorbell pushbutton
because it happened to be ergonomic in that application.
For building projects, it isn’t always convenient to
run connecting wires all the way to a front panel switch
(unleaded it can be done with coax). In that case
it is often easier to switch a DC voltage that controls
switching diodes (or relays), for example when
changing bands and you need to switch several circuits
at the same time.
Basically, if you are running over 100 watts, or using
very small switches, you need to pay attention
to the voltage and current ratings. In the upper HF
range, pat attention to lead length.
At QRP or receive signal levels, just about anything
will work.
I have had some cheap switches fall apart when
subjected to heavy-handed use (or slammed in
the car door) but most are suitable for a receiver
sitting on a desk in the shack.