Tips for restricted source in Powershell
Alternatives To Single And Double Quotes
{A}  #Normal Curly Braces; This makes a scriptblock, but the ToString prints the contents
‘B‘  # Left Single Quotation Mark              0x2018
’C’  # Right Single Quotation Mark             0x2019
‚D‚  # Single Low-9 Quotation Mark             0x201a
‛E‛  # Single High-Reversed-9 Quotation Mark   0x201b
“F“  # Left Double Quotation Mark              0x201c
”G”  # Right Double Quotation Mark             0x201d
„H„  # Double Low Quotation Mark               0x201E


PS C:\&gt; {A}
A
PS C:\&gt; ‘B‘
B
PS C:\&gt; ’C’
C
PS C:\&gt; ‚D‚
D
PS C:\&gt; ‛E‛
E
PS C:\&gt; “F“
F
PS C:\&gt; ”G”
G
PS C:\&gt; „H„
H

Yes, these work! But What's better? The quotes single quotes and double quotes act as their respective normal quotes, (') and (&quot;), and {} behave like single quotes ('). Thus:
$x=&quot;A Variable&quot;
‘$x‘
’$x’
‚$x‚
‛$x‛
“$x“
”$x”
„$x„
{$x}

outputs:
$x           # ‘$x‘
$x           # ’$x’
$x           # ‚$x‚
$x           # ‛$x‛
A Variable   # “$x“
A Variable   # ”$x”
A Variable   # „$x„
$x           # {$x}

As a final useful bit; you don't even have to match the starting and ending quotes, so long as they are of the same type (single/double). Meaning these:
‘$x‛
‚$x'
”$x“
„$x&quot;

Are all perfectly valid, and output like so:
$x           # ‘$x‛
$x           # ‚$x'
A Variable   # ”$x“
A Variable   # „$x&quot;

Alternative Dashes and Uncommon Whitespace
In addition to the additional quotes characters above, PowerShell recognizes some special dashes as equivalent to the hyphen (-):
5–4  # EN DASH          0x2013   [–]
3—2  # EM DASH          0x2014   [—]
1―1  # HORIZONTAL BAR   0x2015   [―]

Powershell also recognizes two other uncommon whitespace characters:
NoBreakSpace   0x00A0
NextLine       0x0085

These were found by @ZaelinGoodman's experiment here
If anything changes, or if you want to see the specifics of how these work, you can find the source code for this handling in the PowerShell Github
I made this community wiki, so this list can be freely updated.